Importing File truncates Account name

I have an in-house application in which we print checks, and we created a program to create a Tab-Delimited file with the check transactions, to import into Quickbooks. These checks are from different accounts, so we have a mix of account checks into the files. The problem I am having is that for the accounts with long names (30+ characters), it truncates the account name when importing, so a new account is created instead of putting the transactions into the corresponding quickbooks account. Do you know whay is this happening?