illigal exception when walking from one wakable area to another

[Sinitrena]

i've got this message when I tested to walk from one wakable area to another:

Illegal exception:
An exception 0x0000005 occured in ACWIN.EXE at EIP=0x00421918; program pointer is +333, ACI version 2.61.747, gtags (0, 91)

As I mentioned above I tried to walk from one area to another with my main character. The second wakable area has a zoom level 90% and the first one 100%. I'm not sure if it has something to do with this, but I thought I should mention it. With an other character than my main character it worked. I tried it a few times and now it works fine but I don't know why. When  I tried it a few days ago it also worked fine and I didn't change anything in this room.

[Pumaman]

Do you have anti-aliasing enabled in Setup? If so, can you try disabling it and try again?

[Sinitrena]

Anti-aliasing was always disabled.  I tried it again with disabled and enabled anti-aliasing. It works now with both. I've got this message four or five times but then this message didn't appear again. But I changed nothing.

[Pumaman]

Strange ... do let me know if it happens again.