How to capture ICAP headers with tcpdump

tcpdump -A -s 10240 'tcp port 1344 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)' | egrep --line-buffered "^........(REQMOD |RESPMOD )|^[A-Za-z0-9-]+: " | sed -r 's/^........(REQMOD |RESPMOD )/\n\1/g'
Human readable representation of the headers of an ICAP request, using tcpdump
Sample Output 
Date: Thu, 28 May 2015 16:23:55 GMT 
Service: MyDLP ICAP Server 
Connection: keep-alive 
ISTag: "mydlp-icap-rocks" 
Encapsulated: null-body=0 

REQMOD icap://10.232.14.49:1344/REQMOD ICAP/1.0 
Preview: 10 
Host: 10.232.14.49 
X-ICAP-Version: 1.0 
Allow: 204 
X-ICAP-Client: ST ICAP Client v.1.0 
Encapsulated: req-hdr=0, req-body=427 
X-Date: 05-28-2015 
Content-Type: text/plain, charset=ISO-8859-1 
X-Classification: HIGHLY_CONFIDENTIAL 
X-Approval-Given: 1 
Host: sthost 
Content-Length: 6 
X-Timestamp: 19:23:55.596 
Content-Disposition: attachment; filename="body_wap.txt" 
X-Sender-Email: idod@sofia-pso.tumbleweed.com 
X-Recipient-List: idod@sofia-pso.tumbleweed.com 
X-Summary-Description: fdsfds 
X-Application-Owner: fdsfsd

0
By: idodekov
2015-05-29 12:58:27
egrep sed tcpdump tcpdump ICAP
0
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