I upgraded my laptop and a desktop to yesterday's -current.  I'm
now having trouble running certain X applications over ssh.

The laptop uses XFree86 4.4.0; the desktop uses xorg.
I did not upgrade X on either machine.  If I log in from my desktop
to my laptop via ssh (with X forwarding -- it's all done by scripts
that haven't changed), I can't fire up (for example) exmh, acroread5,
or psi.  With the first two, the startup fails completely.  I get

X Error of failed request:  BadAtom (invalid Atom parameter)
  Major opcode of failed request:  18 (X_ChangeProperty)
  Atom id in failed request:  0x182
  Serial number of failed request:  137
  Current serial number in output stream:  138

with acroread5 (via Linux emulation, of course) and

X Error of failed request:  BadAtom (invalid Atom parameter)
  Major opcode of failed request:  18 (X_ChangeProperty)
  Atom id in failed request:  0x184
  Serial number of failed request:  12
  Current serial number in output stream:  15

for exmh (native).  

psi is rather weirder -- I get lots of mesages like this, every few
seconds:

X Error: BadWindow (invalid Window parameter) 3
  Major opcode:  2
  Minor opcode:  0
  Resource id:  0x40

but it fires up.  (The messages continue while psi is running.)  When
I exit, I get 

X Error of failed request:  BadWindow (invalid Window parameter)
  Major opcode of failed request:  2 (X_ChangeWindowAttributes)
  Resource id in failed request:  0x40
  Serial number of failed request:  20747
  Current serial number in output stream:  20767

On the other hand, I can fire up some X applications, such as xterm
and xwininfo.  I can run xmms successfully, but when it exits it says

Gdk-ERROR **: BadAccess (attempt to access private resource denied)
  serial 2977 error_code 10 request_code 102 minor_code 0

I didn't see any such problems with exmh or psi when only the laptop
was upgraded, which tends to implicate something on the desktop.
But I haven't a clue what the problem might be.  (Local psi runs
just fine on the desktop; both run just fine locally on the laptop.)