Why do I get different results when using libiconv over iconv binary?

Here is the sample string that I am using encoded in UCS-2:

abvgdđežzijklmnjoprstćuvhcčdžš1234567890*+;'

When converting UCS-2 to iso ISO-8859-1//TRANSLIT with iconv binary from file to file I get:

abvgd?ezzijklmnjoprstcuvhccdzs1234567890*+;'

Now I want to use libiconv in go project. I am using this library http://ift.tt/1VZ1bwG as bindings for libiconv. But when using bindings I get:

abvgd?e?zijklmnjoprst?uvhc?d??1234567890*+;'

It's like different transliteration rules apply when using library inside go.

I examined go bindings library and everything seems in order; only bytes are passed around so no "loss of information" could happen there.

Is there anything else that I should be aware of when using libiconv? Is there some environment context that could trigger different transliteration behaviour?