This post has been written mostly for completeness sake as mentioned earlier, both EMS and MMS are becoming less important in terms of messaging.
One of the first hurdles for testing EMS and MMS is to obtain compatible handsets. For EMS if the handset is not compatible it just won’t work correctly – this is another reason why EMS never really took off. For MMS, you need at least 2 handsets – one that supports MMS and another that does not. For the MMS capable handset you will also need to download the MMS settings on the handset – check with the operator for details.
For EMS there are a few key aspects to test (a) the message payload is partitioned correctly in the resulting concatenated message (b) the binary message encoding is performed correctly and (c) the message payload is eventually reassembled in the mobile correctly. To check both the partitioning and encoding, it would be best to refer to the aggregator or operator gateway spec. As for testing the message reassembling, just use a EMS capable handset to receive the message – start with messages with smaller number of parts first and proceed to increase their size.
For MMS, there are 2 main parts to the message: (a) an encapsulation markup eg. SMIL and (b) a MIME encoded multimedia file (eg. png, jpg) – this means testing that the markup is correct and the encoding is done correctly. Check with the aggregator’s or operator gateway spec for what encapsulation markup (or if SMIL, which version) it supports.
One more thing to note is that you should both test a MMS capable handset (with correct settings) and one that is not supported. Reason is that not all handsets (even the newer ones) support MMS. For those devices that do not support – a SMS with the URL will be sent. Hence the need to test both cases.