Google has announced a Google Maps for Mobile update in the Google Mobile Help discussions area that fixes the bugs with version 3.0 for Symbian and Windows Mobile devices.
Googler, Christopher, said:
A new version of Maps for mobile is available to download. This update includes many fixes and updates for both Maps and Google Latitude based on your feedback here in the Help Forum.
Please see the following Release Notes for more details about what's been changed in this version or go directly to m.google.com/maps in your mobile browser to download it now: http://www.google.com/support/mobile/bin/answer.py?answer=144115
It seems like early feedback on this release shows that some users of these applications on the devices are still having some issues. If you are having any issues with Google Maps for Mobile on Symbian and Windows Mobile devices this is the place to be.
Forum discussion at Google Mobile Help.