Thank you for all the answers. Here is some clarification:
I do have managerial experience as I am holding a Team Lead position right now. I don't expect to get into team lead's seat right after moving to Poland, but at the very least I'd be looking for a Senior Developer position. I also have deep hands on knowledge and extensive experience with Drupal CMF. I don't know about Poland, but in Ukraine people with Drupal experience are hard to find and usually are better paid than an average PHPer.
Thank you for suggestions about job search, I'll of course go this way, but I don't want to do this right now, because I am going to move not earlier than January-February 2014, or may be even a little later and there is no point in talking to companies at this very moment.
Yes I am aware of the fact that IT salaries in Ukraine are higher than in Poland but it isn't the money I am after. If it was about money, I'd be looking for positions in the USA or Germany. But I'm ok with making less than I do in Ukraine as long as my salary allows us to maintain the same standard of life we are accustomed to in Ukraine (from my experience cost of living in Poland (perhaps except Warszaw) is a little bit (10-15%) lower than in Kyiv).
What percentage of gross salary is net in Ukraine, let's say from 2000 USD per month?
In Ukraine they usually speak about net salaries. So when you see $2000 it usually means $2000.
Also the majority of software developers in Ukraine work with companies not as employees but as independent contractors. The tax for independent contractors is 5%, so even if it was brutto, the netto amount would be $1900. Not much of a difference.