CFWINDOW problem

Can't figure out why in two cfwindows created from main page, calendar in cfinput type="datefield" behaves differently depending on ORDER in which they created. Calendar icon became inactive in the second window if the first one was called and then closed. (The input field is still active for manual data entry). But if main page refreshed it's active again. In the first window the calendar active at any time without refreshing main page and when called in any order. These 2 windows are identical. Bahavior is the same with any settings of cfwindow attriburtes like refreshOnShow (true or false) and others. And if to switch the order of windows creation in main page, the calendar in the other pop-up window became frozen and first one previously inactive works fine. Is it a bug in CF8?
This is code in main page:
<cfajaximport tags="cfwindow, cfform, cfinput-datefield" >
<cfwindow title="WindowName1"
name="MyName1"
height="380"
modal="false"
refreshOnShow="true"
initShow="false"
source="../MySource1.cfm"/ >

<cfwindow title="WindowName2"
name="MyName2"
height="380"
modal="false"
refreshOnShow="true"
initShow="false"
source="../MySource2.cfm"/ >

Calles for pop-up windows:
<a href="#" onclick="javascript:ColdFusion.Window.show(MyName1);">Title 1</a>
<a href="#" onclick="javascript:ColdFusion.Window.show(MyName2);">Title 2</a>

in called windows:
<cfform>
<cfinput type="datefield" name="FieldName1">
.......
</cfform>

<cfform>
<cfinput type="datefield" name="FieldName2">
.......
</cfform>