Gdk-warning from firefox, thunderbird

[Jake Lloyd]

Starting firefox (whether as root or less privileged user) throws this 
warning message:
(firefox-bin:<PID>): Gdk-WARNING **: gdk_property_get(): length value 
has wrapped in calculation (did you pass G_MAXLONG?)

Starting thunderbird does the same thing:
(thunderbird-bin:<PID>): Gdk-WARNING **: gdk_property_get(): length 
value has wrapped in calculation (did you pass G_MAXLONG?)

In both cases, the applications run normally after start-up, without any 
apparent problems.

Searching all the usual suspects, I find the same problem described by 
other users (those are mostly on amd64, though mine is i386)--that is, 
my search turns up questions, but no answers.

I am running:
firefox-1.0.4,1
thunderbird-1.0.2_1

FreeBSD 4.9-RELEASE
XFree86-4.5.0,1
windowmaker-0.91.0

(All but the o.s. are kept up-to-date via cvsup/FreeBSD ports.)

-Jake