Adjusting BGP timers on high-latency links

We're running into a problem getting an iBGP session to remain active
with a remote site connected via a high latency link (VSAT T1). The router
at this end of the link (cisco 7513) also eBGP peers with a couple of
upstream ISP's.

Is there a way to adjust BGP keepalive timers on a per neighbor basis?
Haven't been able to figure out a way under any of CISCO's IOS's version
(we're running IOS 11.x on our boxes).