the file
include/init.inc.php mustn't be included twice, which is apparently what happens. You need to find the reason for that. Coppermine runs fine with any flavor of PHP that is better or equal to PHP4.2.0. Your version (PHP5.3) clearly falls into the category "or better".
link to the gallery is:
http://galleri.modart.no/index.php
It takes ages for that page to load and then times out in the browser, which is no surprise, as your domain appears to be down - it can't even be pinged - here is the trace route:
root@foo:/home/myusername# tracert modart.no
traceroute to modart.no (195.47.247.161), 30 hops max, 60 byte packets
1 fritz.fonwlan.box (192.168.0.1) 2.571 ms 7.923 ms 8.370 ms
2 X.X.X.X (X.X.X.X) 48.460 ms 50.158 ms * [edit: replaced thhe IP address in this line with X, as it's none of your concern)
3 * * *
4 * * *
5 * * *
6 * * *
7 * hbg-bb1-link.telia.net (80.91.248.25) 54.675 ms hbg-bb2-pos6-1-0.telia.net (213.248.65.122) 57.387 ms
8 kbn-bb2-link.telia.net (80.91.252.113) 64.424 ms kbn-bb2-link.telia.net (80.91.254.3) 67.334 ms kbn-bb2-link.telia.net (80.91.249.206) 72.849 ms
9 kbn-b3-link.telia.net (80.91.252.23) 74.098 ms kbn-b3-link.telia.net (80.91.253.200) 77.027 ms kbn-b3-link.telia.net (80.91.252.23) 79.868 ms
10 netgroup-ic-119828-kbn-b3.c.telia.net (213.248.95.30) 82.594 ms 84.794 ms 87.442 ms
11 vl943.ar0.ba.cph.ngdc.net (217.116.255.152) 94.073 ms 95.997 ms 98.410 ms
12 * * *
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Ask your webhost for support on that.