It's a bug. The way it is written, 0 and 1 which would be normal for digitalWrite() are going to be OFF and OFF for strictly digital pins and OFF and NEARLY OFF for PWM pins because the analogWrite() will immediately overwrite the OFF/ON effect of the digitalWrite(). They might as well get rid of the digitalWrite().
The RepRap wiki (G-code - RepRap) says that RepRap firmware only supports values of 0 or 1. It says nothing about the Repetier firmware needing 0 and 255 for OFF and ON. I hope that is documented somewhere.