VIA Strengths scale published scientific work
Searching the web for information on the scale turns up thousands of entries, very few of which are related in any serious way to the scientific investigation of the scale. One of the few is the doctoral dissertation of Dennis P. O’Neil, PhD who did his doctoral research at the Department of Psychology and Neuroscience at Duke University. His dissertation reproduces the entire VIA Strengths scale. Working from that, together with the information published by the International Personality Item Pool and the descriptions in the book by Christopher Petersen and Martin Seligman , it is possible to determine the structure, and hence the scoring key.
Structure and scoring key for the VIA Strengths scale
The scale is conceptually divided into blocks of 24 questions. Each block has one question relating to each of the 24 character strengths and virtues. Importantly, it turns out that the order, within each block, in which the questions relate to a strength or virtue, is identical across blocks. The full scoring key is described in detail in a new publication  in the December 2010 issue of Psychological Reports written by Angela O’Brien-Malone, Rosalind Woodworth and me. The article is available at the D.O.I. link given in the reference.
Help with scoring
Two versions of a spreadsheet for questionnaire scoring are available for download. A version in Open Document Spreadsheet format can be obtained here; and a version suitable for Microsoft Excel can be found here. I shall update and improve the spreadsheets as time permits.
 Petersen, C., & Seligman, M. (2004). Character Strengths and Virtues: A Handbook and Classification. Oxford: Oxford University Press.