Enhanced prompt resets

Hi
I use [this](bash git prompt ubuntu) to enhance my bash with git status information, but if I use afpre my bash completely resets to the default (OS X) one.

```
✔ ~/privat/emock [master|✔]
19:16 $ ~/Downloads/afpre-0.9.8/afpre
password:
token expired - need to renew...
AFP| mymac:emock boo$
```

Any idea why? :)