Question : Problem: Can a project developed in Java J2me run successfully on most mobile devices?

We need to develop a small application that will store user info,  pull up a particular url,  automatically input user name and password.  We need to have this run on Mobile Windows,  Blackberry,  Palm and iPhone units.  Will Java J2me allow me to do this?

Answer : Problem: Can a project developed in Java J2me run successfully on most mobile devices?

As all the devices use different platforms (Java, .NET, Symbian etc) it won't be possible to use one development environment to create an application for all device.

Just so you can have some further reading please review the information below:

BlackBerry devices use JDE and also you can get a Blackberry plug-in for Visual Studio:
http://na.blackberry.com/eng/developers/

Also here are some facts about developing applications on Windows Mobile:
http://msdn2.microsoft.com/en-us/library/ms838180.aspx