Hi Kevin,
We had a similar issue with our SSG350Ms, which were originally running 6.2.0r3. After lots of back-and-forth with JTAC, trying out various things to try and solve the problem, they issued us with a patched version of 6.2.0r4 which increased the maximum number of allowed tasks. This fix has been included in the generally-available releases since 6.2.0r5 - see "Unable to telnet to firewall" in the "Changes to Default Behavior Introduced in 6.2.0r5" section of the release notes.
Looking at the release notes for 6.3.0r2, I see that the issue has been fixed there too - look for item 455868 in the "Addressed Issues in ScreenOS 6.3.0r2" section of the release notes.
Hope that helps.
Regards,
Graeme