UAL 891 Heavy returned to LAX

[Aeromexico687]

I was listening to the LAX Tower feed this afternoon (Monday Oct 5th) and a little after 21:10Z I heard UAL 891 inbound., Tower asked them to confirm that they were not declaring an emergency, they said they were not declaring it but requested the emergency vehicles to be available, you can hear this at the Live ATC archive of the above mentioned date and time, this is the Flight Aware Track:

http://flightaware.com/live/flight/UAL891/history/20091005/2021Z/KLAX/KLAX

Any buddy knows the reason for this return?

[mrhahn]

Possibly hydraulics leak: http://www.avherald.com/h?article=420d3ceb&opt=1