sed programming Help need..

Hi All,
i need to write a script using sed programming to replace a character into string.I mean i have a file with comma(,) seperated and optionally enclosed(").Now the problem is some of field having (") in between string.
example -
"WAIVED/CES "GOOD","WAIVED BASED ON CES & "A" PB","WAIVED BASED ON PB & "A" PAID"

Now i want to write a sed script to replace in between " from field.I mean if there is " in between a field it should replace by space.

Pls help me to sort out the above problem.I m nt much aware in sed prog.


Thanks n advance.
Anwar

Code:

---

$ sed 's/"\([^",]*\),,*\([^",]*\)"/"\1\2"/g'
"hello, world",123,zog
"hello world",123,zog
"hello",world,123,zog
"hello",world,123,zog
"hello,,,,,",world,123,zog
"hello",world,123,zog
",world",123
"world",123
123,456
123,456


---

The blue lines are the responses to typing in various lines (in black)

Actually my requirement is bit different.
Suppose -
"WAIVED/CES "GOOD","WAIVED BASED ON CES & "A" PB","WAIVED BASED ON PB & "A" PAID"

so i want output like
"WAIVED/CES GOOD","WAIVED BASED ON CES & A PB","WAIVED BASED ON PB & A PAID"

i mean all extra quote wil replace by space or (~ char ) also fine for me. I mean

"WAIVED/CES ~GOOD","WAIVED BASED ON CES & ~A~ PB","WAIVED BASED ON PB & ~A ~PAID"

OK, I've shown you how, now you have a go.