The 'Cross' portion of the structure (main lift shaft riser and Sky Bar platform) used to be lit up at night, so it clearly resembled a cross - night and day. After complaints were made, the lights were never used again.
There were rumours circulating circa 2001 and 2002 that a Saudi national of immense wealth offered to buy the building with the aim of destroying it and building a new hotel in its place, because of the Christian connotations of the cross...
FYI - the Sky Bar is the longest single cantilevered supported span structure at roughly 280 meters above the ground. The total height of the structure is (I believe) 321 meters...