piculiar behaviour of float:left

I want to surround a picture by a text as shown:

PICHTURETextTextTextText
PICHTURETextTextTextText
PICHTURETextTextTextText
PICHTURETextTextTextText
TextTextTextTexTextTextText
TextTextTextTexTextTextText

I do this by

<img style="margin-right:12px; float:left" src="picture.gif"><div align="justify"> TextTextText</div>

And then I see this on the IE as wanted. But when I print it - even with print-preview - then I have two
results depending on

margin-right:12px

When I have 2, 5, 7, 10, 13, 16px... then it is okay, but with other figures it prints (and shows with
print-preview):

PICHTURE
PICHTURE
PICHTURE
PICHTURE
TextTextTextTexTextTextTextTex
TextTextTextTexTextTextTextTex
TextTextTextTexTextTextTextTex
TextTextTextTexTextTextTextTex

What is wrong?

Thank you,
Manfred