Price fluctuations and hackers aren't the only challenge facing the virtual currency Bitcoin, with developers pooling funds for a virtual bounty offered to anyone who can fix a bug they fear could hemper take up.

Bitcoin developers and their counterparts backing the younger, rival virtual currency Litecoin have thrown together a virtual bounty worth around $10,000 for anyone who can figure out what's causing a data corruption issue in certain Bitcoin and Litecoin wallets on Macs.

As some first noted several months ago, the introduction of the LevelDB key store database into the Bitcoin-qt client versions 0.8.x (currently at 0.8.5) coincided with a data corruption bug affecting Bitcoin users on Mac OS X machines.

The mystery bug impacts an important component of the wallet since LevelDB is used to store the Bitcoin blockchain, the public ledger of all transactions on the Bitcoin network. It's a pain for users because rebuilding the database can take hours. And since the issue is common to wallets on Mac OS X for both currencies, developers from each camp — who have yet to solve the problem themselves — are hoping to crowdsource an answer.

According to Warren Togami, a developer who contributes to both Bitcoin and Litecoin, the unusual step of offering a sizeable bounty has been taken because the bug is considered critical enough to stifle Bitcoin uptake.

"It is being jointly offered by Bitcoin Developers, the BitcoinTalk forum and Litecoin Developers and donations from the public," Togami told ZDNet.

"Bounties of this type are rarely offered. In this case it is happening due to the sense that the issue is critical enough to slow down adoption of Bitcoin."

Togami posted details of the bounty on the Bitcointalk.org forum last week, noting that Gavin Andresen — a key developer who maintains the Bitcoin-qt client — had pledged five Bitcoin, roughly worth $4,000, to the bounty. In addition, BitcoinTalk has pledged four Bitcoin and public donations so far amount to one Bitcoin. Meanwhile, the Litecoin Developer Team has pledged 200 Litecoin. With Litecoin currently trading at around US$10 and Bitcoin trading at around $800, the total bounty is roughly worth $10,000.

The developers want answers to three main questions, including documentation on how to consistently reproduce the data corruption; an explanation for why it happens; and a fix that can be merged into the Bitcoin master file hosted on the Github core repository store.