Things I learned about MMS clients (so far)

Some obstacles I overcame and that are not readily
obvious from the standards:

1. The Vodafone MMS WAP gateway dislikes fragmented IP packets.
   They obviously get dropped somewhere.
   Conclusion: make sure your SAR segment size is smaller then 
               the GPRS SDU size. 1000 Bytes works for me.

2. The E-Plus MMSC is picky. It does not accept anything but
   application/vnd.wap.multipart.mixed or .related as MMS payload.

3. The E-Plus MMS WAP gateway is very picky. If you send a POST
   request that exceeds the default 1400 Byte SDU size, it will
   reject it. You have to announce larger SDUs with the
   WSP Server-SDU-Size capability field.

Hope this helps others.

Kind regards
  Jörg