He means that WiFi Tether doesnt actually implement a proper Infrastructure Mode hotspot.. its actually somewhere between infrastructire and ad-hoc, as some devices see it as one and others as the other..
It is annoying, but ive not found anything that does it right yet.
3 UK Acer Liquid Metal, Silver, B10 - ROM: Modified Stock 2.3.6
orange ZTE Blade Gen 2 (Converted), Grey, B10 - ROM: CM7 Nightly SBUK Mod
orange HTC Hero - ROM: Modaco v5, Radio:63.18.55.06PU_188.8.131.52
orange HTC TyTN II / Kaiser - ROM: Custom SBUK_V3
orange HTC SPV M3100 / Hermes - ROM: Custom SBUK_V8