I'm running the slush proxy on a wheezy distribution that came pre-installed on a memory card I bought with my pi-B

pi@raspberrypi ~/stratum/stratum-mining-proxy-master $ uname -a
Linux raspberrypi 3.2.27+ #250 PREEMPT Thu Oct 18 19:03:02 BST 2012 armv6l GNU/Linux

pi@raspberrypi ~/stratum/stratum-mining-proxy-master $ head /tmp/stratum.log
2013-04-30 00:18:26,973 INFO proxy jobs. # C extension for midstate not available. Using default implementation instead.
2013-04-30 00:18:27,032 INFO proxy mining_proxy.main # Stratum proxy version: 1.1.2
2013-04-30 00:18:27,034 INFO proxy mining_proxy.main # Trying to connect to Stratum pool at stratum.btcguild.com:3333

I didn't make any notes at the time I installed it, but I'm pretty sure I just followed the instructions in the readme.md

Not sure if I can offer any help (I don't want to fiddle with my current setup to try a reinstall), but I thought you'd like to know that it does work.