+The PEM public key format uses the header and footer lines:
+
+ -----BEGIN PUBLIC KEY-----
+ -----END PUBLIC KEY-----
+
+The B<NET> form is a format compatible with older Netscape servers
+and Microsoft IIS .key files, this uses unsalted RC4 for its encryption.
+It is not very secure and so should only be used when necessary.
+
+Some newer version of IIS have additional data in the exported .key
+files. To use these with the utility, view the file with a binary editor
+and look for the string "private-key", then trace back to the byte
+sequence 0x30, 0x82 (this is an ASN1 SEQUENCE). Copy all the data
+from this point onwards to another file and use that as the input
+to the B<rsa> utility with the B<-inform NET> option. If you get
+an error after entering the password try the B<-sgckey> option.
+