Lets say my RTC build definition is called "TestBuild" and I assign my Jenkins RTC plugin with this build definition.
Moreover, I accept new changes prior each build, and hence a new snapshot is created in the used repository workspace.

However, the name of this snapshot is "TestBuild_" and is lacking the build number (either from RTC or Jenkins)
Hence, all snapshots have the same name.

This behavior can also be seen in the posted YouTube tutorial video on jazz.net