dns_rdata_fromtext Syntax Error for "\" in bind-9.8.2

[Harshith Mulky]

Hello All,

I have a Zone file Configured like this wiht the below NAPTR Record.
I have an issue while loading the Zone File
Bind Version I am Running is bind-9.8.2-0.17.rc1.el6.x86_64

While Loading the Zone file, it gives the following syntax Error
"
dns_rdata_fromtext: psx64.com:16: syntax error
zone psx64.com/IN: loading from master file psx64.com failed: syntax error
zone psx64.com/IN: not loaded due to errors.
"
I see it is basically not able to handle \\ in sip:\\1

How do I make the bind Server to just handle this "backslash"? 
Why would not the bind server accept this?

$TTL    0
$ORIGIN psx64.com.
@  IN               SOA  picardvm2.psx64.com. root.psx64.com.  (
                                2002022401 ; serial
                                3H ; refresh
                                15 ; retry
                                1w ; expire
                                3h ; minimum
                               )
; Name Server (NS) records
psx64.com.              IN  NS  picardvm2.psx64.com.
; A records
picardvm2.psx64.com.      IN  A   10.54.48.68
; NAPTR records

4.2.5.4.1.1.5.4.8.9.1.psx64.com.        IN  NAPTR 100 10 "u" "E2U+sip" "!^.*$!sip:\\1 at sonusnet.com;user=phone!" .
 		 	   		  
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