git so alias - error when signing off a patch

I get an error "Syntax error: Unterminated quoted string" when signing off a patch using git so 1:

root@bd603d73e26d:koha(bug21479)$ git so 1  
f() { c=`expr $1 - 1`; git filter-branch -f --msg-filter "cat && echo \"  
Signed-off-by: David Nind <david@davidnind.com>\" HEAD~$c^..: 2: f() { c=`expr $1 - 1`; git filter-branch -f --msg-filter "cat && echo \"  
Signed-off-by: David Nind <david@davidnind.com>\" HEAD~$c^..: Syntax error: Unterminated quoted string

Not sure whether this is something specific to me or a more general problem.

Resolved by using git config --global --edit and adding an extra slash after email address so that it matches the s alias:

Before:

s  = "!f() { c=`expr $1 - 1`; git filter-branch -f --msg-filter \"cat && echo \\\"\nSigned-off-by: David Nind <david@davidnind.com>\\\"\" HEAD~$c^..; }; f"
so = "!f() { c=`expr $1 - 1`; git filter-branch -f --msg-filter \"cat && echo \\\"\nSigned-off-by: David Nind <david@davidnind.com>\\"\" HEAD~$c^..; }; f"  

After:

s  = "!f() { c=`expr $1 - 1`; git filter-branch -f --msg-filter \"cat && echo \\\"\nSigned-off-by: David Nind <david@davidnind.com>\\\"\" HEAD~$c^..; }; f"
so = "!f() { c=`expr $1 - 1`; git filter-branch -f --msg-filter \"cat && echo \\\"\nSigned-off-by: David Nind <david@davidnind.com>\\\"\" HEAD~$c^..; }; f"  

env entry for name:

GIT_USER_EMAIL=david@davidnind.com  
GIT_USER_NAME=David Nind