OE 6.0 sends incomplete messages

Hello.

I am using Outlook Express 6.0 on a Windows XP PC. I have configured the following setting: Tools->Options->Send-> HTML (mail sending format / encode text using quoted printable).

The problem I have is that whenever I send a long text message 5-6 paragraphs, for some reason outlook express trims it and delivers only the first 3 paragraphs.

I check the SENT ITEMS folder and I noticed that the message is stored there incomplete.

Any ideas how to increase the number of characters in outlook express in order to send more paragraphs of text using HTML mail sending format?

If I use plain text the problem is solved.

Thank you in advance.