Performance problem when launching GUI applications under gnome while connected to VPN

I'm experiencing a severe performance problem starting apps but only when connected to my office VPN. It appears to be related to gnome-session.

I believe the following is the relevant strace from simply starting gnome-terminal (but it's a similar trace for all apps i've tried). And if i understand this trace, the last line i included shows it taking 20 seconds to read /tmp/.ICE-unix/4108. If i'm correct, how can i determine exactly why that is taking so long?

$ grep -v -B 1000 '^\ *0' terminal.trc | egrep 'open|\(10'

 0.000103 connect(10, {sa_family=AF_FILE, path="/tmp/.ICE-unix/4108"...}, 21) = 0
 0.000134 fcntl64(10, F_SETFD, FD_CLOEXEC) = 0
 0.000023 write(10, "\0\1\0\0\0\0\0\0", 8) = 8
 0.000051 read(10, "\0\1\0\0\0\0\0\0", 8) = 8
 0.000020 write(10, "\0\2\1\1\6\0\0\0\0\0\0\0\0\0\0\0\3\0MIT\0\0\0\3\0001.0\0\0\0"..., 56) = 56
 0.000085 read(10, "\0\3\0\0\1\0\0\0", 8) = 8
 0.000037 read(10, "\0\0\0\0\0\0\0\0", 8) = 8
 0.000021 write(10, "\0\4\1\1\3\0\0\0\20\0\0\0\0\0\0\0\241%\240.\370\304tl\211\347\343\27\216\0\247\343", 32) = 32
 0.000056 read(10, "\0\6\0\0\2\0\0\0", 8) = 8
 0.000024 read(10, "\3\0MIT\0\0\0\3\0001.0\0\0\0", 16) = 16
 0.000027 fcntl64(10, F_GETFD)      = 0x1 (flags FD_CLOEXEC)
 0.000018 fcntl64(10, F_SETFD, FD_CLOEXEC) = 0
 0.000019 fstat64(10, {st_mode=S_IFSOCK|0777, st_size=0, ...}) = 0
 0.000037 fcntl64(10, F_GETFL)      = 0x2 (flags O_RDWR)
 0.000021 write(10, "\0\7\1\0\7\0\0\0\1\1\0\0\0\0\0\0\4\0XSMPtl\3\0MIT\0\247\343"..., 64) = 64
 0.000051 read(10, "\0\3\0\0\1\0\0\0", 8) = 8
 0.000022 read(10, "\0\0MIT\0\0\0", 8) = 8
 0.000020 write(10, "\0\4\1\0\3\0\0\0\20\0\0\0\0\0\0\0\241%\240.\370\304tl\211\347\343\27\216\0\247\343", 32) = 32
 0.000099 read(10, "\0\10\0\1\3\0\0\0", 8) = 8
 0.000046 read(10, "\7\0GnomeSM\0001.\6\0002.16.0\0\0\0\0", 24) = 24
 0.000035 write(10, "\1\1\1\0\1\0\0\0\0\0\0\0\0\0\0\0", 16) = 16
 0.000369 read(10, "\1\2\0\1\6\0\0\0", 8) = 8
20.935982 read(10, "%\0\0\0001075ba94be000127498096700000"..., 48) = 48

$ uname -a

Linux vm 2.6.18-194.3.1.0.2.el5 #1 SMP Wed May 26 10:20:56 EDT 2010 i686 i686 i386 GNU/Linux

$ gnome-session --version

Gnome gnome-session 2.16.0

Thanks