What scope and probing method are you measuring with?
150 || 390 = 108 ohms, a good termination for ribbon cable and twisted pair (often used for parallel port cables). This is relevant when the port is open circuit (output disabled, presumably input mode). The 74ABT family is more than capable of driving the piss out of such a termination, so it can be ignored in output mode.
The pull-up wouldn't seem to matter, or more importantly, that they should be disable-able along with the 390s to save current consumption.
150 ohms termination (alone) wouldn't be a bad termination either (only a 50% mismatch, not really enough to corrupt the logic levels), though the fact that the Thevenin source voltage is quite high (i.e., the full 5V) may be annoying for most TTL drivers and possibly for long cables (i.e., pulling up so much on an active-low output may violate the V_IL(max) at the receiver end, thus giving bad data).
Are you sure just the 390s are on the jumper, and not the other way around, or both?
Tim