Mouse behaviour in Linux (Cadence)

Hi All,
I am running Cadence Schematic composer on Linux. I am including some
system details below:

1. cadence release is IC500
2. OS is redhat 7.2 / kernel: 2.4.7-10
3. X windows version is: 4.1.0 running sawfish windows manager over
gnome1.2.13
4. Display/Graphics Card:

The problem: All the pop-up windows go on the desktop panel, instead of
staying below the mouse pointer or on the schematic window. By 'pop-up'
windows I mean the windows resulting from commands issued inside the
Schematic composer ('Design Properties <q>" , "Descend Hierarchy<e>",
"Create Instance <i>" )

With the same cadence installation, I do not see this problem when I
am running on Solaris with CDE.

Thanks in advance:

-- Alex.