RFC822 Text Display Problems

We have a database which contains emails mailed in from the internet. The Subject field contains RFC822 Text. Using the Notes 5.0.12 client everything works perfectly. Using 7.0.2 we get some black blocks within the text.

If a formula is used to display the Subject field eg.

@If(@IsResponseDoc; " "; “”)+Subject

then the result is truncated and only the portion after the black boxes is displayed.

Has anybody seen anything like this before and is there a solution ??

TIA,

Mark.