due to an infamous IE bug (not properly obeying z-index rules for select boxes)
our popup calendar (like all other popup we use) doesn't cover underlying select
boxes on IE6. a forum member provided this patch:
http://www.icefaces.org/JForum/posts/list/0/2475.page#15953

.iceCalIFrameFix {
   z-index: -1;
   position: absolute;
   display: block;
   filter: mask();
 }

Index:
component/src/com/icesoft/faces/component/selectinputdate/SelectInputDateRenderer.java
===================================================================
---
component/src/com/icesoft/faces/component/selectinputdate/SelectInputDateRenderer.java
(revision 424)
+++
component/src/com/icesoft/faces/component/selectinputdate/SelectInputDateRenderer.java
(revision 426)
@@ -226,13 +226,14 @@
                         .setAttribute(HTML.ID_ATTR, clientId + CALENDAR_POPUP);
                 calendarDiv.setAttribute(HTML.NAME_ATTR,
                                          clientId + CALENDAR_POPUP);
- calendarDiv.setAttribute(HTML.STYLE_ELEM,
- "display:none;position:absolute; ");
+ calendarDiv.setAttribute(HTML.STYLE_ATTR,
+
"display:none;position:absolute;overflow:hidden;");
                 Element table = domContext.createElement(HTML.TABLE_ELEM);
                 table.setAttribute(HTML.ID_ATTR, clientId + CALENDAR_TABLE);
                 table.setAttribute(HTML.NAME_ATTR, clientId + CALENDAR_TABLE);
                 table.setAttribute(HTML.CLASS_ATTR,
                                    selectInputDate.getCalendarOutlineClass());
+ table.setAttribute(HTML.STYLE_ATTR, "position:absolute;");
                 table.setAttribute(HTML.CELLPADDING_ATTR, "0");
                 table.setAttribute(HTML.CELLSPACING_ATTR, "0");
                 // set mouse events on table ICE-369
@@ -243,6 +244,8 @@
                 String mouseMove = selectInputDate.getOnmousemove();
                 table.setAttribute(HTML.ONMOUSEMOVE_ATTR, mouseMove);
                 calendarDiv.appendChild(table);
+ Text iframe = domContext.createTextNode("<!--[if lte IE
6.5]><iframe class=\"iceCalIFrameFix\"></iframe><![endif]-->");
+ calendarDiv.appendChild(iframe);
                 root.appendChild(calendarDiv);
                 // render a hidden field to manage the popup state; visible ||
hidden
                 FormRenderer.addHiddenField(facesContext, getHiddenFieldName(