I have a number of SPA303 phones in office perfectly works with LDAP (OpenLDAP), all of them 7.4.9 fw.
I just recently upgraded couple of phones to the newest 7.5.4 and now the phone freeze up while the LDAP request.
I enter letters into "First name" or "Last name" fields, pick search and the "Searching the LDAP... or something" appears and the phone lock up on this string. The only way is hardware reboot (power cycle).
Obvious bug.