+There are two ways to encode arbitrary extensions.
+
+The first way is to use the word ASN1 followed by the extension content
+using the same syntax as ASN1_generate_nconf(). For example:
+
+1.2.3.4=critical,ASN1:UTF8String:Some random data
+
+1.2.3.4=ASN1:SEQUENCE:seq_sect
+
+[seq_sect]
+
+field1 = UTF8:field1
+field2 = UTF8:field2
+
+It is also possible to use the word DER to include arbitrary data in any
+extension.