if you have application with correlation rule on specific attribute and you want to ignore case sensitive, just update the CorrelationConfig object from Debug page:
<CorrelationConfig name="ADCorrelation">
<AttributeAssignments>
<Filter ignoreCase="true" operation="EQ" property="email" value="mail"/>
<Filter operation="EQ" property="cuPersonalNumber" value="employeeID"/>
</AttributeAssignments>
</CorrelationConfig>