> For this I need the dates on which HTTrack releases were
> made. history.txt only gives release details and not 
dates.

The debian changelog will give you these details, but only 
from 3.22-1 (December 2002) (HTTrack was created in may 
1998)

See: 
<http://packages.debian.org/changelogs/pool/main/h/httrack/httrack_3.33.13-1/changelog>

And in my backup filetree, I can find:

09-06-99 : 1.25beta
01-05-2000 : 2.02
02-05-2000 : 2.50beta
04-05-2000 : 2.50beta
06-03-2001 : 3.00-RC-10
06-05-2002 : 3.20-beta-4
06-10-2001 : 3.08
06-12-2000 : 3.00-BETA-5d
08-05-2000 : 2.50beta
09-05-2000 : 2.50beta
09-07-2000 : 3.00-ALPHA-11
09-09-2000 : 3.00-ALPHA-26
11-06-2000 : 3.00-ALPHA-4
13-05-2000 : 2.50-ALPHA
14-05-2000 : 3.00-ALPHA-0002
14-05-2001 : 3.02
14-07-2000 : 3.00-ALPHA-12
14-10-2001 : 3.08-2
14-11-2000 : 3.00-BETA-4
15-12-2001 : 3.10
17-07-2000 : 3.00-ALPHA-13
18-08-2001 : 3.06beta
21-02-2001 : 3.00-RC-8
21-09-2002 : 3.20-2
22-10-2000 : 3.00-BETA-2e
23-06-2001 : 3.03
28-12-2000 : 3.00-RC-02
29-05-2000 : 3.00-ALPHA-0003
29-10-2002 : 3.21-7
30-04-2000 : 2.02
30-05-2000 : 3.00-ALPHA-1
30-06-2002 : 3.20RC3
30-08-2000 : 3.00-ALPHA-24
31-05-2000 : 3.00-ALPHA-1