A system and method for expiring a software module on a wireless communication device is disclosed. Following a process of designating an element for removal from a data-structure, conditional limitations are used to determine if immediate freeing of the element from memory is available. As such, for non-stability critical program code, the performance benefits of having multiple redundant execution units are preserved, yet in the instances where fault tolerant or stability critical execution is desired for certain program code, the redundant execution units may be repurposed to provide greater assurances as to the fault-free execution of such instructions. Thereby, it can be prevented that the diffracted light is emitted from the reflection preventive patterns of the transparent plate. The invention specifically relates to a method for isolating -4–1,3-oxazolidin-2-one hydrochloride of desired purity by separating the undesired inorganic side products such as stannous hydroxide by manipulation of pH at different stages and finally treating with N,N-dimethylamino butyraldehyde diethyl acetal in an acidic medium to provide Zolmitriptan conforming to regulatory specifications.