Error converting String to Date

Hi all,
I'm trying to build a date from a number of text boxes on a form, and then insert into a Datetime field in Sql Server

string PO = PDay.Text + "/" + PMonth.Text + "/" + PYear.Text + " " + PHour.Text + ":" + PMinute.Text + ":" + "00";
       
DateTime PublishOn = DateTime.Parse(PO);
My insert always fails, and I have the following error line:
25/02/2009 01:59:00 Incorrect syntax near '01'.
Can anyone see what the problem is with the date I have above? I'm in Europe so use the day/month format as opppsed to the US month/day.

Thanks
Melt

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