If it is for paper, then it very probably is Dektol. As said before, Microdol-X and Dektol will be significantly brown when mixed if bad. Xtol doesn't necessarily turn color when it goes, so I personally wouldn't mess with Xtol that old, though you could certainly mix it and do a test.
I assume what you have is Microdol-X rather than the older Microdol, which I don't imagine even came in packets. I've still got some around, and it is a nice developer, but not something that seems all that useful for me anymore with Xtol around. Obviously it does have a following and the older stuff does too.