PDF Preview does not look the same as through Acrobat

Except for one text field, all of my other text fields with "Appearance" set to "Underline" are appearing without the underline.

Here's a cut from a screen shot of the preview in LiveCycle Designer ES 8.2.1.4029.1.523496

and here's a cut from a screen shot of the same pdf document opened in Acrobat (I did this test from my Mac too with the same results, so I know it's not a computer related issue):

Can anyone explain the discrepency here? I could use borders instead of Appearance, but the border goes across the entire field instead of just the place where a user can enter text, so I'd like to avoid that if possible.

Here's the XML of one of the fields... seems fairly straight forward:

         <field name="contactName" y="22.225mm" x="105.286mm" w="91.564mm" h="4.318mm">
            <ui>
               <textEdit>
                  <border hand="right">
                     <edge presence="hidden"/>
                     <edge presence="hidden"/>
                     <edge/>
                     <edge presence="hidden"/>
                     <?templateDesigner StyleID aped1?></border>
                  <margin/>
               </textEdit>
            </ui>
            <font typeface="Myriad Pro"/>
            <para vAlign="middle"/>
            <traversal>
               <traverse ref="streetAddress[0]"/>
            </traversal>
            <caption reserve="29.0972mm">
               <value>
                  <text>Contact Name:</text>
               </value>
               <font typeface="Myriad Pro"/>
               <para vAlign="middle"/>
            </caption>
            <border>
               <edge presence="hidden"/>
               <corner presence="hidden"/>
            </border>
         </field>