The Abit IP35-Pro, for one example, includes 2 built-in eSATA ports.
They are both controlled by the JMicron controller chip.
If you're wanting to put in your own eSATA bracket and connect to an internal Intel SATA port, that (AHCI hot swap support) should work better than with the ICH8 south bridge SATA ports.
Can't confirm that's so, however.