Edit the file .pinerc (in your home directory) and search for
the line:

# Your default printer selection
#printer=attached-to-ansi

and replace line
printer=[] mp | lw -ps
with
printer=[] mp | lp
or 
printer=[] mp | lp -dchase-mailroom

replace line
personal-print-command=[] mp | lw -ps
with
personal-print-command=[] mp | lp
or
personal-print-command=[] mp | lp -dchase-mailroom