How to Known if there error for a property

[Rodolfo =?iso-8859-1?Q?Garc=EDa_Esteban=2FCYII?=]

Hi,

I´m using struts 1.2.4, after validate a form. I need to know if there is 
a message for a property before print, how can I do?

Thanks in advance,

Rodolfo