The web.page.regexp is not parsing the whole output for the regular expression. It only checks the first line for the regular expression. This happened when updating to 2.2.5
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zabbix_get -s x10468.rz2012.adm.denic.de -k web.page.regexp[10.121.50.145,business-de/public/domain/denic.de,8811,".*"]
HTTP/1.1 200 OK
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correct output would be
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zabbix_get -s x10468.rz2012.adm.denic.de -k web.page.get[10.121.50.145,business-de/public/domain/denic.de,8811]
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
X-Request-UUID: AUdevdge-SmXh-info.de.rz.1
Content-Location: http://10.121.50.145/business-de/public/domain/denic.de
Content-Type: application/xml
Content-Length: 713
Date: Tue, 22 Jul 2014 15:43:25 GMT
Connection: close

<domain-registration domain="denic.de"><status>CONNECT</status><changed>2013-03-01T10:56:26+01:00</changed><detailed-contacts-in-role href="./denic.de/detailed-contacts-in-role"></detailed-contacts-in-role><tech-c><contact href="../contact/tech/DENIC-1000006-DBS"></contact></tech-c><zone-c><contact href="../contact/zone/DENIC-1000006-DBS"></contact></zone-c><nameservers><nameserver owner="denic.de." host="ns1.denic.de."><glue>2a02:568:121:6:2:0:0:2</glue><glue>81.91.170.1</glue></nameserver><nameserver owner="denic.de." host="ns2.denic.de."><glue>193.171.255.36</glue></nameserver><nameserver owner="denic.de." host="ns3.denic.de."><glue>87.233.175.19</glue></nameserver></nameservers></domain-registration>
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