Callback function within SCN with Advanced Networking enabled

[IPOMakingMeInsane]

There seems to be inconsistency with the way the callbacks work within an SCN where users will log onto remote sites. I have tested the callback function (Programmed under button programming on 5610,5410 handsets)

Site A extensions 200 - 220
Site B Extensions 300 - 320

Callbacks will work on extensions on the same site e.g.

1) Site A Extn 200 logged on Site A to Site A Extn201 logged on Site A
2)Site A Extn 200 logged on Site A to a Site B Extn 300 logged on Site B and vice versa
3)Site A Extn 200 logged on Site A to Extn 301 logged on Site A

Callback fails in the following circumstance

4)Site B Extn 300 logged on Site B to Site B Extn 301 logged on Site A although all extns on Site A are able to callback Site B extn 3001 that is logged on Site A.

Phew! This took a while. Hopefully someone out there has understood my method of explaining the issue.Is there a way of fixing point 4.

Also is there a way of getting the Callback, Vmail, Camp On menu as one does when a soft key Button is programmed to a user when the user is busy. I am trying to add another feature to the soft keys but I have no more availble soft keys and if a way was found for any busy extn to bring up this menu I could remove the Callback feature from the button programming for all handsets and add the breakout function which I need.