Stack overflow while closing the main form

[Cigydd]

Hi delphists,

I'm engaged in developing a complex application (an economical
information system).
When I close the main form using the Close method called from a menu
click event handler, I get the Stack overflow error.
Then an Access violation appears and I can locate the source line at
which it happens from the Assembler window: it's the Forms unit, line
4660, in TCustomForm.Release.
But else no clue how to debug this. The VCL code is invisible for the
debugger :-(

I would much appreciate any help with this problem.

--Cigydd