<div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">How can I setup a custom field validation and have if so that it can be blank, OR match my regular expression<div>
<br></div><div>Currently I have: (?#YYYY-MM-DD HH:mm:ss)^[12]\d{3}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$</div><div>
<br></div><div>Really what I guess what I think I'm looking for is /(^[12]\d{3}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}$|^$)/</div>
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