94 cabriolet sludge question

[Kneale Brownson]

At 02:13 PM 01/18/2003 -0500, AV8oR wrote:
>I am helping to maintain a friends 94 cabrio V6.
>I changed the oil yesterday and found a creamy tan sludge on
>the bottom of the oil filler cap. A look at the drained oil  - BLACK
>no bubbles! Is this an antifreeze pin hole leak?
>The coolant level has been constant for the last 2 months!
>
>I was just wondering - she got really scared that she needed
>a new engine.

Moisture in the oil from short trips?