I just compiled a PBP program using the MeLabs USB serial programmer for the 16F88 on internal clock. I selected the 16F88_04 from C:\Program files\Mecanique\MCSP\MCLoader\16F88\16F88_04.

Call up the CONFIG word (click the 'C' beside the PIC16F88 dropdown) and there you can select the various clock modes you want.

In your code you will need an OSCCON statement to select 4 MHz and possibly a speed tweak via OSCTUNE.

Seems to work for me.

HTH
BrianT