oracle traffic PPTP problem

Hi,

we are having problem with some remote computers which are connected via PPTP (both sides are mikrotik), all other traffic is passing through VPN normal, only problem is when remote computer is pulling some information from server which is on central location, tcp 1521 port, it is taking too long to get all information from the server. if on remote computer we tell the aplications to get information via dyndns (over the internet without VPN) information are passed in few seconds (via VPN few minutes), there is no any restriction in firewall, there is no any additional traffic, bandwith is also not an issue. Same thing via VPN and the Internet, same request, everything is the same…

Any suggestion??

Thanks

update…

i tried to connect my aplication from remote site via Interent (port forward) to central location and it is working, so the problem is in PPTP VPN. I also changed MTU/MRU on mirkotik to 1372, problem still exist, I removed “dynamically change MSS” from mangle (turn off on pptp server)and after that manually remove that rules in mangle, problem still exist. only if I coming via Internet than it works perfectly. Does Mikrotik has some problem with PPTP/MTU or something??

I have the same problem here, please help…