nixCraft

sub: PPS not being used
I am using
Kernel :2.6.23rc2
PPS patch: ntp -pps-2.6.23rc2.diff
NTP version: ntp-4.2.4P4
I have enabled PPS support as a module.under this I have selected PPS debugging message,UART serial support.
I am using GPS Receiver TRIMBLE ACE 3 .
PPS from GPS receiver is fed to MAX232.and output of MAX232 is fed to DCD pin of serial port.the serial port I have used is ttys3.
The relevant part of my ntp.conf is
server 127.127.20.3 mode 138 prefer iburst
fudge 127.127.20.3 refid TSIP time1 0.042 flag3 1 flag2 0
These are the results after about half an hour:
ntpq -p
remote refid st t when poll reach delay offset jitter
========================================
====================================
==
xGPS(0) .TSIP. 0 l 39 64 377 0.000 -35.67 35.234
ntptime
ntp_gettime() returns code 0 (OK)
time c812205b.41762000 Sun, May 14 2006 22:32:11.255, (.255709),
maximum error 719516 us, estimated error 44711 us
ntp_adjtime() returns code 0 (OK)
modes 0x0 (),
offset 19886.000 us, frequency -390.653 ppm, interval 4 s,
maximum error 719516 us, estimated error 44711 us,
status 0x1 (PLL),
time constant 2, precision 1.000 us, tolerance 496 ppm,

Information for generic driver is coming in log file.But no info regarding PPS is coming in log file.
But if I am runing the ppstest file I can see PPS data.

What could be the possible reason for PPS not being used?
Please feel free to ask if any more details is required...