How to validate sharepoint datetime control?

I am using sharepoint datetime control,开发者_C百科 and when i use range,regular or some other validation controls, every time error message will show up when input wrong format (this is right), but after that when i input right date, this error message won't disappear, it stays there, can't remove... (problem happened)

Is there any other way like javascript to validate it?

Set Display="Dynamic" for the validation control.