SED conflicting with shell script special char

File 'aa' has path to some files. If it starts with './' then I want to replace it with the current directory. For eg
File aa
-------
./10211/abc.txt
./10347/def.txt

I want to transform it into
File bb
-------
/home/avs/abc.txt
/home/avs/def.txt

where '/home/avs' is the current working directory [pwd] I have written this script

#LOGIC TO REPLACE . WITH PWD
ppwwdd="$PWD"
sed -e 's/\.\//'"$ppwwdd"'/g' aa > bb

When I run the script it gives the error
sed: command garbled: s/\.\///home/avs/g

I think because sed is not able to recognize special character of forward slash '/' it is giving the error. Any way to get out of this.

Thanks
Sunil

When you do a sed command like this:
sed 's/cat/dog/'
it is not required that you use slashes as the separator character. This would would just as well:
sed 's=cat=dog='
Your problem is that you are using slashes as the separator character and slashes also appear in the value contained in your variable. The easiest solution is to switch to another separator character.

Great. It worked.
I knew about this but forgot to use. Thanks a lot

sed -e 's=\.\/='"$PWD"'=g' aa > bb

yes avs, the = trick is ok, but
a) instead of:
sed -e 's=\.\/='"$PWD"'=g' aa > bb
try:
sed "s=\.\/=$PWD=g" aa > bb
b) i prefer the traditional way
PWD=`pwd|sed 's/\//\\&/g'`
and the normal sed:
s "/^\./$PWD/"

NOTA: the correct path of:
./10211/abc.txt
is
/home/avs/10211/abc.txt
not
/home/avs/abc.txt