When does CUPS call for gs?

[angelb at bugarin.us]

I have two slightly diffrent printers: HLPJ4 SI and HP4100 TN

Both printers are configured same in the CUPS server. When I send a Test Page to the SI printer it prints just fine. However, when I send a test page to the TN printer, it prints garbage and while it's doing this, I noticed that it's using gs. See the following output:

[root at stlpr002 cups]# while :; do ps -ef|grep -i lp; sleep 1; done
root     13764 13906  0 17:06 pts/0    00:00:00 grep -i lp
lp       13765   606  0 17:06 ?        00:00:00 y_cc8dl		<===== the SI printer

# everything below this relates to the TN printer
root     13812 13906  0 17:06 pts/0    00:00:00 grep -i lp
lp       13814   606  2 17:06 ?        00:00:00 printers.cgi   	<=== the TN printer
lp       13842   606 10 17:06 ?        00:00:00 ck1f	       	<=== the TN printer

root     13844 13906  0 17:06 pts/0    00:00:00 grep -i lp
lp       13845   606  0 17:06 ?        00:00:00 ck1f 1819 zoe Test Page 1  /var/spool/cups/d01819-001
lp       13846   606  0 17:06 ?        00:00:00 /bin/sh /usr/lib64/cups/filter/pstoraster 1819 zoe Test Page 1
lp       13845   606  3 17:06 ?        00:00:00 ck1f 1819 zoe Test Page 1  /var/spool/cups/d01819-001
lp       13846   606  3 17:06 ?        00:00:00 /bin/sh /usr/lib64/cups/filter/pstoraster 1819 zoe Test Page 1
lp       13847   606  2 17:06 ?        00:00:00 ck1f 1819 zoe Test Page 1

lp       13850 13846 31 17:06 ?        00:00:00 /usr/bin/gs -dQUIET -dDEBUG -dPARANOIDSAFER -dNOPAUSE -dBATCH -dNOMEDIAATTRS \
-sDEVICE=cups -sstdout=%stderr -sOUTPUTFILE=%stdout -

I made the font smaller but I will apologize in advance if it will wrap when it's posted.

Anyway, why did CUPS sent the Test Page directly to the SI printer and it worked great while CUPS called gs to print Test Page to the TN printer? Again, both printers are HP and are using the same CUPS drivers.

Any ideas?

Thanks,
angel