Firefox causing a plugin to crash, which in turn crashes Firefox

When you view two pages in a row that contain content for the same plugin,
the plugin's "terminate" function is called, then the plugin's "initialize"
function is called.  However, the plugin binary is not unloaded and
reloaded.  With our plugin, this causes the global pointers for the
memory-management system to not be set to NULL, so when the plugin is
re-initialized, the plugin dereferences an invalid pointer, causing it to
crash, and in turn, crash Firefox.

If a page with no plugin content is loaded between the two pages with plugin
content, there is no crash.

Is this a known bug, and if so, is there a workaround?  This behavior has
been observed in Firefox 1.5.0.1 for Mac, and 1.0.4 for Mac.  It has not
been observed on Firefox for Windows.

(As a side note, I haven't been able to reproduce this bug in 1.5.0.3:
Firefox crashes at the least hint of anything involving a plugin.)

Thanks,
Mark Wagner