At the moment, my X server (or maybe xterm) is not handling cntrl+mouse
button events properly.  If I try cntl+button2 or cntl+button3 in xterm,
I get a beep, rather than the appropriate menu.  Perhaps related, cntl+q
is not causing acroread to exit.  But cntl+key is working properly in 
xterm and exmh.

I'm running 1.5.3_rc1 with X 4.10.  I *think* I've seen the same on 
some version of -current.

Here's what xev says for cntl+mousebutton:

KeyPress event, serial 18, synthetic NO, window 0x3000001,
    root 0x2f, subw 0x0, time 458079263, (50,5), root:(342,177),
    state 0x80, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    XLookupString gives 0 characters:  ""

ButtonPress event, serial 23, synthetic NO, window 0x3000001,
    root 0x2f, subw 0x0, time 458081945, (50,5), root:(342,177),
    state 0x84, button 3, same_screen YES

ButtonRelease event, serial 23, synthetic NO, window 0x3000001,
    root 0x2f, subw 0x0, time 458083782, (50,5), root:(342,177),
    state 0x484, button 3, same_screen YES

KeyRelease event, serial 23, synthetic NO, window 0x3000001,
    root 0x2f, subw 0x0, time 458084519, (50,5), root:(342,177),
    state 0x84, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    XLookupString gives 0 characters:  ""

I haven't touched my keymap or my .xrdb files in a geological age or 
thereabouts.

		--Steve Bellovin, http://www.research.att.com/~smb
		Full text of "Firewalls" book now at http://www.wilyhacker.com