diff --git a/APPL/PRS/prs_edit_perslid_save.asp b/APPL/PRS/prs_edit_perslid_save.asp
index 2c4640fb9a..aa6d1fc061 100644
--- a/APPL/PRS/prs_edit_perslid_save.asp
+++ b/APPL/PRS/prs_edit_perslid_save.asp
@@ -23,6 +23,19 @@ var xfunc = user.func_enabled("*", null, null, prs_key>0?prs_key:null);
 var prsauthparams = prs.checkAutorisation(prs_key);
 user.auth_required_or_abort(prsauthparams.writeman || prsauthparams.writeuse || prsauthparams.writeself);
 
+var prs_tz = getFParam("prs_tz", S("fac_server_timezone"));
+
+if (prs_tz != "")
+{
+    var sql = "SELECT '' FROM V$TIMEZONE_NAMES"
+            + " WHERE tzname = " + safe.quoted_sql(prs_tz);
+
+    var oRs = Oracle.Execute(sql);
+    if (oRs.EoF)
+        shared.internal_error("timezone (" + safe.html(prs_tz) + ") not found.");
+    oRs.Close();
+}
+
 var fields =  [ { dbs: "prs_srtperslid_key", typ: "key",  frm: "prs_srtkey" },
                 { dbs: "prs_afdeling_key", typ: "key",  frm: "prs_afdkey" },
                 { dbs: "prs_perslid_naam", typ: "varchar",  frm: "prs_naam" },
@@ -42,7 +55,7 @@ var fields =  [ { dbs: "prs_srtperslid_key", typ: "key",  frm: "prs_srtkey" },
                 { dbs: "prs_perslid_tussenvoegsel", typ: "varchar",  frm: "prs_tussen" },
                 { dbs: "fac_profiel_key", typ: "key",  frm: "fac_prkey", track: L("lcl_prs_profile") , foreign: "fac_profiel"},
                 { dbs: "prs_perslid_email", typ: "varchar",  frm: "prs_email", track: L("lcl_prs_person_email") },
-                { dbs: "prs_perslid_timezone", typ: "varchar",  frm: "prs_tz", track: L("lcl_prs_person_timezone") },
+                { dbs: "prs_perslid_timezone", typ: "varchar",  val: prs_tz, track: L("lcl_prs_person_timezone") },
                 { dbs: "prs_perslid_mobiel", typ: "varchar",  frm: "prs_mobiel", track: L("lcl_prs_person_mobile") } ];
 
 if (prsauthparams.writesys || (S("prs_mgt_edit_login")?xfunc.canWrite("WEB_FACMGT"):false))
@@ -118,7 +131,7 @@ if (prs_key > 0)
     }
 
     if (user_key == prs_key)
-        Session("time_zone") = getFParam("prs_tz", S("fac_server_timezone"));
+        Session("time_zone") = prs_tz;
 
     shared.trackaction("PRSUPD", prs_key, (prsUpd.trackarray.length ? prsUpd.trackarray.join("\n") : null) );
 }