bootselector - lame question

[Wojciech Puchar]

sorry but while i use FreeBSD for a long time i need dual boot for the 
first time.

i already have installed DOS in dospartition 1 (/dev/ad0s1) and FreeBSD on 
dospartition 2 slice a (/dev/ad0s2a)

i can boot both but i need to use fdisk to change active partition every 
time i want to boot another system.

how to install some kind of boot menu if possible (i think it is)