[ALUG] Really awkward text parsing shell script question

Ok, I've got a shell script that parses some logfiles. It spits all the lines with an appropriate value using sed:

for i in log_* do sed -n -e '/text/p' "$i" > "/home/mephi/logs/$i" done

The problem I have is that the logfiles aren't quite right and I need to add a value to the 25th item in each line. Other than knowing that value is numeric and 10 characters long, I don't know anything more about it.

running the command: sed -n -e '/text/p' "log _20090814_162009" | awk '{print $25}' gives: 1363231555 1363231555 1363231555 1363231555 1229014082 1229014082 1229014082 1229014082

I need to able to make them look like: 1000000001363231555 1000000001363231555 1000000001363231555 1000000001363231555 1000000001229014082 1000000001229014082 1000000001229014082 1000000001229014082

Can anyone offer any help?

Cheers,

Matt