i just realized two things:
1) i installed this exact motherboard for a friend when he was building a gaming PC. it was on sale at Microcenter for $90 when bought with a CPU. i found the manual for this board laying around from that build. and no, it does not come with a jumper, just like you said. there is also no indication of an existing CMOS reset button. only a reset pin.
2) MSI is retarded.
all you can do at this point is try to hunt down a jumper. it's a pretty standard item even radio shack sells them. at least the used to. if you have a copper cable you can just use that.