I tested it with both, curl and wget and all I get is this html page.
curl (7.31.0) response headers:
HTTP/1.1 307 Temporary Redirect
Location: http://sourceforge.net/projects/simutrans/files/pak64.scifi/pak64.scifi_112.x_v0.2.zip/download?use_mirror=kent
Content-type: text/html
Content-Length: 0
Date: Thu, 08 Aug 2013 22:23:53 GMT
Server: lighttpd/1.4.26
HTTP/1.1 200 OK
Server: nginx/0.8.54
Date: Thu, 08 Aug 2013 22:23:54 GMT
Content-Type: text/html; charset=utf-8
Connection: close
Pragma: no-cache
Cache-Control: no-cache
X-Frame-Options: SAMEORIGIN
X-UA-Compatible: IE=edge,chrome=1
Set-Cookie: VISITOR=xxx; expires="Sun, 06-Aug-2023 22:23:54 GMT"; httponly; Max-Age=315360000; Path=/
Set-cookie: sf.consume=xxx; expires=Tue, 19-Jan-2038 03:41:07 GMT; Path=/
Content-Length: 24136
Vary: Accept-Encoding
wget (1.14) response headers / log:
--2013-08-08 22:23:02-- http://downloads.sourceforge.net/project/simutrans/pak64.scifi/pak64.scifi_112.x_v0.2.zip
Resolving downloads.sourceforge.net (downloads.sourceforge.net)... 216.34.181.59
Connecting to downloads.sourceforge.net (downloads.sourceforge.net)|216.34.181.59|:80... connected.
HTTP request sent, awaiting response...
HTTP/1.1 307 Temporary Redirect
Location: http://sourceforge.net/projects/simutrans/files/pak64.scifi/pak64.scifi_112.x_v0.2.zip/download?use_mirror=garr
Content-type: text/html
Content-Length: 0
Date: Thu, 08 Aug 2013 22:23:02 GMT
Server: lighttpd/1.4.26
Location: http://sourceforge.net/projects/simutrans/files/pak64.scifi/pak64.scifi_112.x_v0.2.zip/download?use_mirror=garr [following]
--2013-08-08 22:23:02-- http://sourceforge.net/projects/simutrans/files/pak64.scifi/pak64.scifi_112.x_v0.2.zip/download?use_mirror=garr
Resolving sourceforge.net (sourceforge.net)... 216.34.181.60
Connecting to sourceforge.net (sourceforge.net)|216.34.181.60|:80... connected.
HTTP request sent, awaiting response...
HTTP/1.1 200 OK
Server: nginx/0.8.54
Date: Thu, 08 Aug 2013 22:23:03 GMT
Content-Type: text/html; charset=utf-8
Connection: close
Pragma: no-cache
Cache-Control: no-cache
X-Frame-Options: SAMEORIGIN
X-UA-Compatible: IE=edge,chrome=1
Set-Cookie: VISITOR=xxx; expires="Sun, 06-Aug-2023 22:23:03 GMT"; httponly; Max-Age=315360000; Path=/
Set-cookie: sf.consume=xxx; expires=Tue, 19-Jan-2038 03:41:07 GMT; Path=/
Content-Length: 24115
Vary: Accept-Encoding
Length: 24115 (24K) [text/html]
Saving to: ‘/tmp/pak64.scifi_112.x_v0.2.zip’
0K .......... .......... ... 100% 172K=0,1s
2013-08-08 22:23:03 (172 KB/s) - ‘/tmp/pak64.scifi_112.x_v0.2.zip’ saved [24115/24115]
Downloading the pak sets manually with a web browser works, so I don't think it is a connectivity problem.