The tweak works as well in ME as it did in 98/SE - and in some cases, better (the maximum value is 512MB (524288) - but most people take teh eqasy way out and use 512000). The value that lgbpop found is not to far from teh 'magic number' that existed for some motherboards in Win98 of 70% of RAM (or of 512MB) - look here for more details.....
http://www.aumha.org/win4/a/memmgmt.htm