UDP source port 0

Hi,

I have to open a connection from UDP source port 0 to UDP destination port 8254.

But the lower service port I can define is 1.

All the packets are always dropped.
2012:11:16-18:30:13 fw ulogd[4600]: id="2001" severity="info" sys="SecureNet" sub="packetfilter" name="Packet dropped" action="drop" fwrule="60001" initf="eth1" mark="0x1000" srcmac="0:22:90:c6:db:da" dstmac="0:c:29:78:5d:34" srcip="178.237.87.12" dstip="10.10.10.10" proto="17" length="1344" tos="0x00" prec="0x00" ttl="61" srcport="0" dstport="8254"

Any idea on how to do ?
Thank you
Regards,
Romano