The most critical component of a dependability benchmark is the faultload, as it should represent a repeatable, portable, representative, and generally accepted set of faults. These properties are essential to achieve the desired standardization level required by a dependability benchmark but, unfortunately, are very hard to achieve. This is particularly true for software faults, which surely accounts for the fact that this important class of faults has never been used in known dependability benchmark proposals. This paper proposes a new methodology for the definition of faultloads based on software faults for dependability benchmarking. Faultload properties such as repeatability, portability and scalability are also analyzed and validated through experimentation using a case study of dependability benchmarking of web-servers. We concluded that software fault-based faultloads generated using our methodology are appropriate and useful for dependability benchmarking. As our methodology is not tied to any specific software vendor or platform, it can be used to generate faultloads for the evaluation of any software product such as OLTP systems.