diff --git a/library/x509_create.c b/library/x509_create.c
index df20ec8..fa66cae 100644
--- a/library/x509_create.c
+++ b/library/x509_create.c
@@ -37,44 +37,46 @@
     const char *name;
     size_t name_len;
     const char*oid;
+    int        tag;
 } x509_attr_descriptor_t;
 
 #define ADD_STRLEN( s )     s, sizeof( s ) - 1
 
+// note: preset tag types as proposed in rfc3280 and widely used
 static const x509_attr_descriptor_t x509_attrs[] =
 {
-    { ADD_STRLEN( "CN" ),                       MBEDTLS_OID_AT_CN },
-    { ADD_STRLEN( "commonName" ),               MBEDTLS_OID_AT_CN },
-    { ADD_STRLEN( "C" ),                        MBEDTLS_OID_AT_COUNTRY },
-    { ADD_STRLEN( "countryName" ),              MBEDTLS_OID_AT_COUNTRY },
-    { ADD_STRLEN( "O" ),                        MBEDTLS_OID_AT_ORGANIZATION },
-    { ADD_STRLEN( "organizationName" ),         MBEDTLS_OID_AT_ORGANIZATION },
-    { ADD_STRLEN( "L" ),                        MBEDTLS_OID_AT_LOCALITY },
-    { ADD_STRLEN( "locality" ),                 MBEDTLS_OID_AT_LOCALITY },
-    { ADD_STRLEN( "R" ),                        MBEDTLS_OID_PKCS9_EMAIL },
-    { ADD_STRLEN( "OU" ),                       MBEDTLS_OID_AT_ORG_UNIT },
-    { ADD_STRLEN( "organizationalUnitName" ),   MBEDTLS_OID_AT_ORG_UNIT },
-    { ADD_STRLEN( "ST" ),                       MBEDTLS_OID_AT_STATE },
-    { ADD_STRLEN( "stateOrProvinceName" ),      MBEDTLS_OID_AT_STATE },
-    { ADD_STRLEN( "emailAddress" ),             MBEDTLS_OID_PKCS9_EMAIL },
-    { ADD_STRLEN( "serialNumber" ),             MBEDTLS_OID_AT_SERIAL_NUMBER },
-    { ADD_STRLEN( "postalAddress" ),            MBEDTLS_OID_AT_POSTAL_ADDRESS },
-    { ADD_STRLEN( "postalCode" ),               MBEDTLS_OID_AT_POSTAL_CODE },
-    { ADD_STRLEN( "dnQualifier" ),              MBEDTLS_OID_AT_DN_QUALIFIER },
-    { ADD_STRLEN( "title" ),                    MBEDTLS_OID_AT_TITLE },
-    { ADD_STRLEN( "surName" ),                  MBEDTLS_OID_AT_SUR_NAME },
-    { ADD_STRLEN( "SN" ),                       MBEDTLS_OID_AT_SUR_NAME },
-    { ADD_STRLEN( "givenName" ),                MBEDTLS_OID_AT_GIVEN_NAME },
-    { ADD_STRLEN( "GN" ),                       MBEDTLS_OID_AT_GIVEN_NAME },
-    { ADD_STRLEN( "initials" ),                 MBEDTLS_OID_AT_INITIALS },
-    { ADD_STRLEN( "pseudonym" ),                MBEDTLS_OID_AT_PSEUDONYM },
-    { ADD_STRLEN( "generationQualifier" ),      MBEDTLS_OID_AT_GENERATION_QUALIFIER },
-    { ADD_STRLEN( "domainComponent" ),          MBEDTLS_OID_DOMAIN_COMPONENT },
-    { ADD_STRLEN( "DC" ),                       MBEDTLS_OID_DOMAIN_COMPONENT },
+    { ADD_STRLEN( "CN" ),                       MBEDTLS_OID_AT_CN,              MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "commonName" ),               MBEDTLS_OID_AT_CN,              MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "C" ),                        MBEDTLS_OID_AT_COUNTRY,         MBEDTLS_ASN1_PRINTABLE_STRING },
+    { ADD_STRLEN( "countryName" ),              MBEDTLS_OID_AT_COUNTRY,         MBEDTLS_ASN1_PRINTABLE_STRING },
+    { ADD_STRLEN( "O" ),                        MBEDTLS_OID_AT_ORGANIZATION,    MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "organizationName" ),         MBEDTLS_OID_AT_ORGANIZATION,    MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "L" ),                        MBEDTLS_OID_AT_LOCALITY,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "locality" ),                 MBEDTLS_OID_AT_LOCALITY,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "R" ),                        MBEDTLS_OID_PKCS9_EMAIL,        MBEDTLS_ASN1_IA5_STRING},
+    { ADD_STRLEN( "OU" ),                       MBEDTLS_OID_AT_ORG_UNIT,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "organizationalUnitName" ),   MBEDTLS_OID_AT_ORG_UNIT,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "ST" ),                       MBEDTLS_OID_AT_STATE,           MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "stateOrProvinceName" ),      MBEDTLS_OID_AT_STATE,           MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "emailAddress" ),             MBEDTLS_OID_PKCS9_EMAIL,        MBEDTLS_ASN1_IA5_STRING },
+    { ADD_STRLEN( "serialNumber" ),             MBEDTLS_OID_AT_SERIAL_NUMBER,   MBEDTLS_ASN1_PRINTABLE_STRING },
+    { ADD_STRLEN( "postalAddress" ),            MBEDTLS_OID_AT_POSTAL_ADDRESS,  MBEDTLS_ASN1_PRINTABLE_STRING },
+    { ADD_STRLEN( "postalCode" ),               MBEDTLS_OID_AT_POSTAL_CODE,     MBEDTLS_ASN1_PRINTABLE_STRING },
+    { ADD_STRLEN( "dnQualifier" ),              MBEDTLS_OID_AT_DN_QUALIFIER,    MBEDTLS_ASN1_PRINTABLE_STRING },
+    { ADD_STRLEN( "title" ),                    MBEDTLS_OID_AT_TITLE,           MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "surName" ),                  MBEDTLS_OID_AT_SUR_NAME,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "SN" ),                       MBEDTLS_OID_AT_SUR_NAME,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "givenName" ),                MBEDTLS_OID_AT_GIVEN_NAME,      MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "GN" ),                       MBEDTLS_OID_AT_GIVEN_NAME,      MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "initials" ),                 MBEDTLS_OID_AT_INITIALS,        MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "pseudonym" ),                MBEDTLS_OID_AT_PSEUDONYM,       MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "generationQualifier" ),      MBEDTLS_OID_AT_GENERATION_QUALIFIER, MBEDTLS_ASN1_UTF8_STRING },
+    { ADD_STRLEN( "domainComponent" ),          MBEDTLS_OID_DOMAIN_COMPONENT,   MBEDTLS_ASN1_IA5_STRING },
+    { ADD_STRLEN( "DC" ),                       MBEDTLS_OID_DOMAIN_COMPONENT,   MBEDTLS_ASN1_IA5_STRING },
     { NULL, 0, NULL }
 };
 
-static const char *x509_at_oid_from_name( const char *name, size_t name_len )
+static const x509_attr_descriptor_t *x509_at_oid_from_name( const char *name, size_t name_len )
 {
     const x509_attr_descriptor_t *cur;
 
@@ -83,7 +85,7 @@
             strncmp( cur->name, name, name_len ) == 0 )
             break;
 
-    return( cur->oid );
+    return( cur );
 }
 
 int mbedtls_x509_string_to_names( mbedtls_asn1_named_data **head, const char *name )
@@ -92,6 +94,7 @@
     const char *s = name, *c = s;
     const char *end = s + strlen( s );
     const char *oid = NULL;
+    const x509_attr_descriptor_t* oid_attr = NULL;
     int in_tag = 1;
     char data[MBEDTLS_X509_MAX_DN_NAME_SIZE];
     char *d = data;
@@ -103,12 +106,13 @@
     {
         if( in_tag && *c == '=' )
         {
-            if( ( oid = x509_at_oid_from_name( s, c - s ) ) == NULL )
+            if( ( oid_attr = x509_at_oid_from_name( s, c - s ) ) == NULL )
             {
                 ret = MBEDTLS_ERR_X509_UNKNOWN_OID;
                 goto exit;
             }
 
+            oid = oid_attr->oid;
             s = c + 1;
             in_tag = 0;
             d = data;
@@ -127,13 +131,18 @@
         }
         else if( !in_tag && ( *c == ',' || c == end ) )
         {
-            if( mbedtls_asn1_store_named_data( head, oid, strlen( oid ),
-                                       (unsigned char *) data,
-                                       d - data ) == NULL )
+            mbedtls_asn1_named_data* cur = mbedtls_asn1_store_named_data( head, oid, strlen( oid ),
+                                                                (unsigned char *) data,
+                                                                d - data );
+
+            if(cur == NULL )
             {
                 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
             }
 
+            // set tagType
+            cur->val.tag = oid_attr->tag;
+
             while( c < end && *(c + 1) == ' ' )
                 c++;
 
@@ -192,29 +201,19 @@
  *
  *  AttributeValue ::= ANY DEFINED BY AttributeType
  */
-static int x509_write_name( unsigned char **p, unsigned char *start,
-                            const char *oid, size_t oid_len,
-                            const unsigned char *name, size_t name_len )
+static int x509_write_name( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data* cur_name)
 {
     int ret;
     size_t len = 0;
+    const char *oid             = (const char*)cur_name->oid.p;
+    size_t oid_len              = cur_name->oid.len;
+    const unsigned char *name   = cur_name->val.p;
+    size_t name_len             = cur_name->val.len;
 
-    // Write PrintableString for all except MBEDTLS_OID_PKCS9_EMAIL
-    //
-    if( MBEDTLS_OID_SIZE( MBEDTLS_OID_PKCS9_EMAIL ) == oid_len &&
-        memcmp( oid, MBEDTLS_OID_PKCS9_EMAIL, oid_len ) == 0 )
-    {
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_ia5_string( p, start,
-                                                  (const char *) name,
-                                                  name_len ) );
-    }
-    else
-    {
-        MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_printable_string( p, start,
-                                                        (const char *) name,
-                                                        name_len ) );
-    }
-
+    // Write correct string tag and value
+    MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_any_string( p, start, cur_name->val.tag,
+                                                                (const char *) name,
+                                                                name_len ) );
     // Write OID
     //
     MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( p, start, oid, oid_len ) );
@@ -239,9 +238,7 @@
 
     while( cur != NULL )
     {
-        MBEDTLS_ASN1_CHK_ADD( len, x509_write_name( p, start, (char *) cur->oid.p,
-                                            cur->oid.len,
-                                            cur->val.p, cur->val.len ) );
+        MBEDTLS_ASN1_CHK_ADD( len, x509_write_name( p, start, cur ) );
         cur = cur->next;
     }