My M10empacman looks like:
#!/bin/sh
/drive0/empacman

IIRC, I had that exact same problem due to CR+LF (0x0D+0x0A) pairs in my M10empacman script.
Assuming you created the script on a Windows PC, one simple way to check is to open a DOS window on your PC where you have a copy of the script and issue the following commands:

debug M10empacman<ret>
d<ret>

You should get something like this if everything is ok:
-d
XXXX:0100 23 21 2F 62 69 6E 2F 73-68 0A 2F 64 72 69 76 65 #!/bin/sh./drive
XXXX:0110 30 2F 65 6D 70 61 63 6D-61 6E 0A xx xx xx xx xx 0/empacman.

(ignore the X's)

If you do have this problem you can use a text editor like Textpad and save the file as type 'Unix'.