*** Description of problem:
Currently the only format for the callbacks property inside the context is:
Please consider supporting also another common format which is:
callbackClass1, callbackClass2, ..., callbackClassN.
*** Additional info:
Lookup is made in ClassCacheManager#buildCommandCallback(CommandContext, ClassLoader)
fixed by making sure the classnmes of the callback are trimmed
Verified on 6.1.0.DR2