If they are Cat5 cables with all 4 pairs wired they should get higher than the speed you get. The Cat5 specification may say only 100M, but when written this only involved using 2 pairs of the four. Cat5 cables with a 4 pairs will, in most circumstances give you 1G ok. I have some long drops of AT&T high quality Cat5 cables that are years old and still give 1G all the time. Cat5e will certainly give you 1G, although I have seen many faulty Cat5e cables where one of the wires is broken/not connected correctly and they were working at 100M. There is a lot of difference between specification and real world use.
Tudor There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2