While "text" may not be considered a verb by all, the majority of people use it as such. Therefore, it should be treated like other regular verbs that end in a 't' or 'd' sound. Paint goes to painted, wait goes to waited, mend goes to mended, paste goes to pasted. Yes, there are verbs such as "find" and "fight" that have irregular past tense forms, but unless the speakers of common English are going to come up with an irregular past tense for for "text", then we should go with what makes sense....TEXTED. The reason we add a second syllable to these verbs ending with 't' or 'd' is so that we can mark the tense change so people know we are referring to a time in the past. Using "fax" as an example does not make any sense, because fax ends with an /s/ sound not a /t/ sound. Just because there is an 'x' in "text" does not make it the same as all other words that have 'x' them.