TOOLTIP IN DROPDOWNLIST

Hellow all forumn member,

how can  i set tooltip in Dropdownlist.

suppose in my DDL i bound it from Database.so at the pageLoad time record are binded in DDL.but some record are inside in DDL .i want to set ToolTip over it.so how can i set a Tooltip in my DDL.

Pls solve my problem

Thanking You.
...