I have created a list of tables by using custom styles for the table
captions. The style applied to the TOC entries is the built-in TOC
style "TOC 7".
The field code looks like this {TOC h\t "my_caption_style; 7"}

I have modified the built-in TOC 7 style with a hanging indent and
corresponding tab ( I correctly modified the TOC 7 style settings, I
did not perform explicit formatting)

Everyhing is working fine, but whenever I update this list of tables
the first line does not get indented and I have to manually indent the
first line (i.e. after "Table x"), e.g.

Table 1: Sales projection for the years
          2004 - 2006
Table 2: Interest paid on foreign debt for 2005

But it should look like this after each update:

Table 1:   Sales projection for the years
          2004 - 2006
Table 2:   Interest paid on foreign debt for 2005

Is it possible to create a macro which asks how many entries there are
in the TOC and then indents the first line at the appropriate place?

Help is appreciated. Thank you very much in advance

Andreas