OpenBSD 5.8: compile fails

Good afternoon list,

I am trying to compile the most recent version of pgAdmin on OpenBSD
5.8. config runs fine, but make throws the following errors and fails:

pgAdmin3.cpp:1757:35: error: images/pgAdmin3-16.pngc: No such file or
directory
pgAdmin3.cpp:1758:35: error: images/pgAdmin3-32.pngc: No such file or
directory
pgAdmin3.cpp:1759:30: error: images/splash.pngc: No such file or directory
pgAdmin3.cpp: In constructor 'pgAppearanceFactory::pgAppearanceFactory()':
pgAdmin3.cpp:1780: error: 'pgAdmin3_32_png_img' was not declared in this
scope
pgAdmin3.cpp:1781: error: 'pgAdmin3_16_png_img' was not declared in this
scope
pgAdmin3.cpp:1782: error: 'splash_png_img' was not declared in this scope
*** Error 1 in pgadmin (Makefile:5565 'pgAdmin3.o')
*** Error 1 in pgadmin (Makefile:3568 'all')
*** Error 1 in . (Makefile:617 'all-recursive')
*** Error 1 in /home/mkoch/Downloads/pgadmin3-1.22.0 (Makefile:477 'all')

This happens with 1.20.0, 1.22.0 and 1.22.1

Compiling 1.18 from the provided OpenBSD ports tree succeeds, though.

Wondered if anybody could nudge me into the irght direction...?

TIA
Matthias
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