CaseIgnoreListMatch evaluates to TRUE if and only if the attribute value and the assertion value have the same number of strings and corresponding strings (by position) match according to the caseIgnoreMatch Matching Rule.
In X.520, the assertion syntax for this matching rule is defined to be:
SEQUENCE OF DirectoryString {ub-match}
That is, it is different from the corresponding type for the PostalAddress syntax. The choice of the Postal Address syntax for the assertion syntax of the caseIgnoreListMatch in LDAP should not be seen as limiting the matching rule to apply only to attributes with the Postal Address syntax.