How long can you go with a phono cable?

I was wondering whether there a length beyond which you would not want to go with a phono cable. I see most cables are 1.0 - 1.5 m. Is it because of the low voltage produced by the cartridge?
The industry standard is 1.25 meters in length, although we have made cables up to 2 meters in length that have worked very well in this application. As a matter of fact we once had a gentleman who needed a 3 meter run and we were just as supprised as im at how good it worked and sounded.
Until it finds out that you've been also making good music with a 0.5m orchid digital w/XLR ends!
I agree with Rives and Theo. Don't forget about shielding, very important on a phono cable