One fix for VFP9 SP2 has just been released:
FIX: The toolbar on an SDI form is disabled in Visual FoxPro 9.0 Service Pack 2
http://support.microsoft.com/kb/948528/en-us
Good news is when they say: "This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Visual FoxPro 9.0 service pack that contains this hotfix."