Problem with source natting udp/5004

Dear Mikrotik community,

Having src-nat rule, masquerading everything from 192.168.88.0/24, and when passing udp traffic having source port of 5004, it just wont nat.

I guess 5004 is somehow reserved for the mikrotik itself, but isn’t it supposed to change the source port also in such cases ?

I guess static source port natting would workaround the problem, but still seems like a bug in the OS.

Anyone faced such kind of issue ?

Please export and post the NAT rules.

Just simple masq rule, nothing special.

[admin@Mikrotik] /ip firewall nat> export

jul/28/2012 00:57:47 by RouterOS 5.16

software id =

/ip firewall nat
add action=masquerade chain=srcnat disabled=no out-interface=ether1
src-address=192.168.10.160/28 to-addresses=0.0.0.0


But when trying to pass udp traffic with source port of 5004, it just wont work. Can say that by looking at the active connections, as well as torching the outgoing interface..