[R] .Internal(filledcontour()) - ancient history or just plain wrong?

[Raphael Päbst]

Hello everyone!
In my ongoing odyssey through badly dokumented and sparingly commented
R-code, I've come across something that baffles me.
The following line of code

.Internal(filledcontour(as.double(x), as.double(y), z,
as.double(levels), col = col))
 not surprisingly results in an error, telling me that there is no
such function as filledcontour().
The code this comes from has been written for an older version of R,
probably 2.5.x so I was wondering, if the error results from me using
a current version (3.1.0) or if the author wanted to use
filled.contour() and forgot the '.'.

Would that in fact help or was there something called filledcontour()
that has changed into something else nowadays?

I've tried to contact the author, but he hasn't used R for at least
five years and hasn't replied so far, so I'm hoping soeone here can
give me a hint to the solution of this problem.

Many thanks in advance!

Raphael