How to connect SMSC server using SMPP from PHP

[eluser]Sudz[/eluser]
I am trying to connect SMSC server using SMPP from PHP to send and receive sms. It would be easy if I can find some good php classes or already built script so that I don't have to bother in details?

so, does anyone have experience with this or at least can suggest me which php class or script to use?