running fetchmail from mutt in the background

[cga2000 <cga2000@xxxxxxxxxxxxx>]

I have bound the G key to the following command in my .muttrc:

"!fetchmail -v -k -m '/usr/bin/procmail -Yf- &'\n"

I was hoping that the '&' would cause this process to execute in the
background but it seems that this is not working as I expected: 

fetchmail gives me some errors and apparently does not fetch anything.

I got rid of the '&' and everything works fine but I was wondering if
there was any way I could run fetchmail on demand in the background.

Thanks,

cga