The problem happens sending several SMSs (5-10 or more) to a series60 device (all S60 2nd and 3rd Edition devices). The WMA unsinged midlets using PushRegistry acts wrongly when launching. We can have:

• Slow queuing of received SMSs;
• Symbian OS Error;
• Launching fails;
• Crash of application without message or error.

The solution claimed by the Forum Nokia is the signing of the Midlet with the Third Party Protection Domain and change the permissions for the autostart to "always allowed".

It is not a easy solution (the sign process is always a pain) and also it is a pity that the affected feature is one of the most interesting for J2ME developers.

Link to the Forum Nokia Knowledge Base article.