Funny symbol next to battery meter after ActiveSync

[Guest Y-Wing]

I have line 1 and line 2 on my E200. I have found that when I connect via ActiveSync the "1" or the "2" to the immediate left of the battery meter gets replaced by a circle with a vertical line down the middle whenever you go into an application, e.g. calendar. Carries on after I have disconnected.

Anybody else seen this and can explain? It goes away when you re-boot the phone but comes back next ActiveSync connection.

Cheers!