UPS Packages Sit in Customs for Months

Recently, I used UPS Express Cargo to send a package, and it arrived in the country on the 23rd. After sending off all the required paperwork for customs clearance, I have heard nothing as of today, December 31. In spite of customer service's assurances that the relevant department would work expeditiously, I have yet to receive any definitive word on when I can expect to begin withdrawing my funds. After more than five working days, I'm getting very impatient with the customs clearance procedure. How long it will take to get my shipment cleared by customs if it takes more than a week to complete the tax payment is anyone's guess. As far as international shipping goes, this has been the slowest process I've ever dealt with.