[Openswan Users] NAT-T Initial Contact IKEv1 Configuration

[SVM]

Hello, all!

Stuck with the problem in configuring NAT-T to make it work using UDP:4500.

I mean, how to force IKE exchange to use NAT-T UDP:4500, instead of 
regular UDP:500?

forceencaps=yes as I suppose works only for ESP-packets.
nat-traversal=yes

Simple topology:
  - transport mode
  - left side(openswan) has global unicast ip
  - right side(mikrotik) has full one2one nat rfc1918 address to global 
unicast.


There is option to use nat-t in mikrotik and it sends udp:4500, but my 
openswan replies to UDP:500, instead of UDP:4500 and 500 port doesn't 
pass provider's nat on the right side, but 4500 does!

Also if I set openswan to initiate connection - it also uses UDP:500 for 
IKEv1, not UDP:4500.

Am I wrong in something? or I just don't know what is the real problem.

Please help.

-- 
SVM