Building a RS-232 fiber converter?

With the talk of 20mA converters, it reminds me to ask... is there a simple schematic for a basic RS-232 to fiber media converter? In the real world, I'd just pick a pair up at a Hamfest (or get a mate for the single-fiber AT&T converter I have at home)... here, though, with no planes due in for almost six months, it's make it or do without. I can harvest the ST-connector LEDs/phototransistors from a box of soon-to-be-discarded AUI-to-10BaseFL transceivers, and I do have enough MAX232-type chips that I can easily do it from a single supply... the question just becomes... what goes in the middle? The station here is wired with CAT5(e?) and fiber (mostly multimode, but some single mode)... it would be handy for me here to be able to have some remote serial thingies without depending on terminal servers/reverse telnet, etc.... just a small box with a DB25 or DE9 connected to another via fiber. 19200 bps would be great, but even 4800 bps would be better than nothing. Anyone have any ideas on how to construct such a beast? I can build pretty much anything from a schematic or even a napkin, but I'm not really a designer. If it's as simple as hooking an LED to the TTL output of a MAX232, and the phototransistor to the input of a MAX232, that'd be super, but I suspect that there might need to be a little more to it than that. Thanks for any input/direction/etc -ethan