timePicker.ControlSource='this.VFPDate'

*on timePicker class:

DEFINE CLASS myTimePicker ...
VFPDate=NULL
VFPControlSource = "myTable.MyField"

PROCEDURE VFPDate_Access
  RETURN EVL(NVL(EVALUATE(m.this.VFPControlSource),{}),"")
ENDPROC

PROCEDURE VFPDate_Assign
LPARAMETERS pickValue
  REPLACE (m.this.VFPControlSource) WITH m.pickValue
ENDPROC