Android Question Mailparser and eMail in WebView

I am using TOP 10 to find a signature that would identify mail suitable for parsing as MultipartBody. I have simply been using "multipart" with not very good results. Is there a more appropriate signature I should be looking for?

Also messages with Encoding base64, parsed as SimpleBody, come through the parser as 0 byte. Is this a format the Mailparser cannot parse? Any help greatly appreciated.

Best regards