No buffer space available

I have an SQL file with a set of about 3000 insert statements. This
file is executed twice from a remote client machine running Windows
XP. The first time it is executed against a Windows 2003 Server
running PostgreSQL 8.0. The second time it is executed against a
Windows 2003 Server running PostgreSQL 8.2. This setup has been in
place for about a year now and never had any issues.

However, I noticed today that all the file executions fail with
[nativecode=could not send data to server: No buffer space available
(0x00002747/10055)] error.

I attempted to run the same file using pgAdmin III version 1.6.2, but
every time the file is executed the only return in messages pane is
the colon sign ":". No data is inserted.

I attempted to run the same file using psql.exe and this worked
without any problems.

I also noticed that if I use less inserts, for example only a few
hundred, the file executes fine.

What could be the issue?

Thank you.

Nik