20 min early datetime rows to pull in conditionalsplit

hi all,

i have a column fldEnterDatetime(ex:2012-04-26 06:37:32.000)

i want to seperate the data which is 20 min before the GetDate().

so im passing like this in conditional split transformation

fldEnterDateTime==DATEADD(MI,-20,getdate())

my fldEnterDatetime column datatype is datetime only.

can some one suggest me the Condition to filter this