Not quite a pool, and not cheap, but CEO and Terrace suites at the IC HK have a outdoor jacuzzis (and amazing views).

Terrace Suite
Room rate : HKD27,300 + 10% service charge per room per night
Total : 4,500 square feet
Location: 16th Floor
View: Full Victoria Harbour overlooking Hong Kong Island

* A sexy and stylish one-bedroom suite (4500 sq. feet)
* Large outdoor terrace with sunken Jacuzzi and day beds overlooking Victoria Harbour and Hong Kong Island.
* Four poster king-sized bed with the finest linens and celestial fiber optic overhead mood lighting
* Latest in-room technology including a Sharp 45" LCD television with Bose Lifestyle 38 DVD home entertainment system.
* 37" Sharp LCD Colour TV with Cable / Satellite TV channels in the bedroom
* Romantic bathroom with Jacuzzi and rain forest shower for two
* Spacious marbled bathroom
* Shower cubicle with steam

CEO Suite
Room rate : HKD45,000 + 10% service charge per room per night
Size: 5,000 square feet
Location: 14th Floor
View: Full Victoria Harbour overlooking Hong Kong Island

*A spectacular two-bedroom suite (5000 sq. feet)
* Large outdoor Private Terrace with sunken Jacuzzi overlooking Victoria Harbour and Hong Kong Island
* Living Room with dining area accommodating 8 persons with wet bar for entertaining.
* Master bedroom with en suite marble bathroom with Jacuzzi, steam room and rain forest shower
* Latest in-room technology including a Sharp 45" LCD television with a Bose Lifestyle
* Spacious white marbled bathroom
* Large sunken Jacuzzi bathtub
* Shower cubicle with steam