c# dates and Java

I m trying to invoke Java web service from C#.
There is a date involved.

When I use C# I get a parsing error. When I use Java client
it works fine.

Here is what the dates looks like on the wire
C#   2003-08-30T10:15:45.0000000-04:00
Java 2003-08-30T15:02:54.902-04:00

How do I format the C# date into the Java format (The milli second
precision seems to be causing the problem).

Help anyone ?

Thanks in advance
=sam