Oops, I forgot to mention that the usps does actually find a match for the test Cities, the reuslts look like:

<PRE>
<b>MISHAWAKA IN</b><br>is associated with the    For these ZIP Codes,
ZIP Code<br>following ZIP Codes:      the city name is:
Type<br>-------------------------------------------------------------<
+BR>
<BR>46544 ACCEPTABLE (DEFAULT)       STANDARD<BR>
<BR>46545 ACCEPTABLE (DEFAULT)       STANDARD<BR>
<BR>46546 ACCEPTABLE (DEFAULT)       STANDARD<BR></PRE>
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Good Day