Error Trapper Failing...

Hey guys,

I'm just having a few issues with an error trapper in a MIRROR LISP routine I have. Just wondering if someone wouldn't mind taking a quick look.

The error trapper works OK for an ESC at most steps through the routine, but it seems to fail after the line I have highlighted bold/blue in the code below:

(defun err (s)
(command "u")
(prompt "\n*Program Terminated*")
(setq *error* exi)
(princ)
)

(defun c:mi ( / MIss MIpt1 MIpt2 OROS)
(SETQ OROS (GETVAR "OSMODE"))
(SETQ ORORT (GETVAR "ORTHOMODE"))
(COMMAND "undo" "BE")
(SETVAR "OSMODE" 0)
(SETVAR "ORTHOMODE" 1)
(SETVAR "cmdecho" 0)
(COMMAND "undo" "END")
(setq exi *error*)
(setq *error* err)
(setq MIss (ssget))
(setq MIpt1 (getpoint))
(command "ucs" "O" MIpt1)
[b] [color="blue"](setq MIpt2 '( 0 0 0))[/color][/b]
(command "mirror" MIss "" MIPT2 pause pause)
(command "ucs" "P")
(SETVAR "OSMODE" OROS)
(SETVAR "ORTHOMODE" ORORT)
(SETVAR "cmdecho" 0)
(princ)
)

If I hit ESC anytime after the line in blue... the error trapper doesn't seem to activate.

I haven't really had much experience with error handling in the past. To be honest, I've had some bad experiences with UNDO>MARK/BACK resulting in everything in the session being undone, and have been scarred off (UNDO>BACK frightens me, haha).

Looking forward to hearing back.

Thanks for any help.