I am looking for a DSLR that is capable of 5fps .
I like sports photography, landscape, and night.
My camera right now is dimage z3 a 12x zoom.
And i want a high iso for low light/indoor.
my price range is under 1000$.
And i have some old pentax lenses.

Well the cheapest DSLR I know of with 5fps is a Nikon D200.

This will be a little over budget before thinking about lens.

Next step down would be a D80 which is 3fps for about 13 jpegs or 6 NEF.

My D200 will shoot 5fps in jpeg for about 60 shots.

DSLR or SLR is not only body. More expensive are lenses, especially good lenses. Remember that kitlenses are so so. I think even not average quality. I experienced it with my Sony Alpha. So you should think first about Pentax one.

D200..Thats what I use...But the D300 which is coming out in November will be 6fps. I suggest you be patient and wait.

Pentax unfortunately does not make any current DSLR's with the specs you've requested. Also, finding a brand new D200 for around $1000 could be hard...try looking on eBay for a used D200 as most of these owners will probably be upgrading to the new (and much better IMO) D300. I think that going with the "old" D200 would be your best bet for now...than upgrade a few years later.