SparkCoin withdrawals have been enabled again following a community takeover of SPARK and resolution of its forked blockchain. I reset pending cashout requests and set everyone's automatic withdrawal threshold to 100,000 SPARK to prevent unintentional automatic withdrawals going to an old/forked wallet. I've also cleared everyone's saved withdrawal address, just to make sure you don't withdraw to an old address by mistake.
Please confirm that wherever you are withdrawing to is on the correct blockchain! Bittrex is still working on it so it is disabled there, and Bter has enabled trading but is not taking deposits for it last I heard.