Bingbot is using a differently-formatted date. Avoid an exception.

[dmcassel]

Bingbot's "If-Modified-Since" field looks like "131445406060000000".

[kcoleman-marklogic]

Certainly the change looks fine. Go fer it.

My only concerns is whether any callers will fall over if they get nothing back from parseDate. I only found one (though I may not know all the rocks to look under), and it looks like it will still function.

[dmcassel]

I traced through the code and the empty sequence is an acceptable response.