In build 62488, there is much less leaking but it is still
present.  Build 62110 leaked about 2.5 MB per window created
and closed.  Build 62488 leaks about 130 - 200 KB per main
development window created and closed.  So it is an order of
magnitude better but still not completely fixed.  I suggest
use of Solaris Modular Debugger (mdb) as documented in another
report to find where the memory that is still held at exit
was allocated from.  Or maybe you have other tools you can
use on other platforms.  I'm pretty sure part of this is
related to GTK and might even be due to underlying GTK bugs
(they seem to have a lot of memory leaks in that code), which
might not be easy to work around.