I try to get firstday of the month and end day of the month using the code below. 

If 'RentalStart' is March, the outcome suppose to be 1/3/2013 and 31/3/2013 

But what I am getting is 1/3/2013 and 28/3/2013 

Can anybody tell me is this a bugs or my script below is wrong... 

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tmpdate=getComponent("RentalStart").getValue();

var s1:NotesDateTime = session.createDateTime(tmpdate);

 document1.setValue("RentalFrom",s1.getDateOnly());

s1.adjustDay(-1);

s1.adjustMonth(1);

document1.setValue("RentalUntil",s1.getDateOnly());

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Thank you in advance to you guys...