Trapdoor Logarithms and US Gov't

Not sure how many of you are familiar with PGP encryption (it's used on many linux/un*x based systems, and you can get PGP on your home box, too...)

Anyway, I remember reading about how PGP employs trapdoor logarithms. TL's are, essentially, logarithms used to encode data, but cannot be reversed (hence the name "trapdoor" - you can fall through one, but can't get out..)
I believe that these trapdoor logarithms function on matrix mathematics. In matrix algebra, functions are not communative. (Communative properties are, in regular math, addition and multiplication - that is, 5+4 = 9, as does 4+5...Order doesn't matter.)
However, in matrix mathematics, functions are not communative. As a result, you can proceed forward, but any attempt to reverse the equation is impossible.

That said and done, I was discussing with one of my cohorts the other day about a US Government program, supposedly peddled to foreigners, which is able to reverse these logarithms.

Of course (and evidently!), my knowedge of this is quite shakey. Has anyone else heard of this? I am 99% sure that these trapdoor logarithms utilise matrices. Any info anyone has about the development of such a reversal, or even anything about governmental involvement in cryptology would be excellent.

Danke.