Compiz: often have to reload WM

[sMash!]

i have a small problem. well, really an irritation. i often find that my compiz/emerald will fail and i'll have to reload the window manager; this seems to happen [alot] when i'm working across multiple workspaces, and with certain apps running. in particular, Document Viewer and Synaptic, but sometimes others. for instance, i had to reload compiz three times in as many minutes today while viewing a pdf, running a package download, and using FF. is this common?

Toshiba A75
P4 3.2GHz, 1.125MB DDR2
ATI Radeon 9100
Intrepid Ibex