Migrating from SENDMAIL on SUN SOLARIS to POSTFIX on Linux

Migrating from sendmail on SUN Solaris to POSTFIX on Linux.
I have been asked to migrate our sendmail to postfix on Linux and would appreciate and information. Hints and tips on the process involved.
Perhaps any links to useful site or documentation that you may know about.

Many Thanks

Can you give us a little background on the driving forces behind the migration?

I ask because Postfix does run on Solaris x86, and Sendmail does run on Linux. Which of the 100s of Linux distros did you have in mind?)

It seems aggressive to change both out at once. (Personally I would just change the MTA out, as Postfix runs great on Solaris.)

Thanks for the reply.
Sorry unable to response before.
Anyway - Running Red Hat Enterprise Rel4 Update4
Need to move away from SUN towards HP/Linux.
Postfix was chosen by our previous SNR Admin but now hes left.
Picking up the pices and moving forward.
I though I could "migrate" sendmail over and run a "convert utlity" to auto convert from sendmail to postfix?
I hear this tool has available.
Do you know about it.