Where does PATH at login come from?

[Richard Steinberger]

When I log on to some of our BSD unix machines (Alliant, Multiflow,
DEC 3100), I notice that the PATH variable has some initial members,
usually something like (/usr/ucb /usr/bin /bin .).  Can anyone
let me know where these initial elements of PATH come from?
Is this at all configurable?  Thanks to any and all who reply.

regards,

	ric steinberger
	ric at ace.sri.com