"The riots were encouraged by round-robin text messages." El Reg
"The protests were fuelled by text messages urging people to join in." BBC
Says who? The government that just ordered the censoring? Of course they're going to blame public disturbance on shady criminal elements instead of, for instance, pissed off poor people wondering about where their next meal is going to come from.
It's not a fact that is sourced to the Mozambican media outlet nor the BBC journalist, yet it's critical to understanding the issue. The reasonableness of the censorship depends on the nature and degree of risk the blockaded messages present.
This report casts doubt on the claim that text messages were sent encouraging riot but were in fact planning for protests - just like anywhere and just like Iranians were encouraged to do with Twitter: http://allafrica.com/stories/201009090012.html
"Note that they are not restricting all phone texting, but only to those that are using 'burn' phones or 'pre-paid' wireless phones since these tend to be the phones which are sending the texts."
If you think that the kind of people who are upset because the price of their staple foods has gone up are going around buying disposable phones to spread misinformation, you're completely deluded. You know that GDP per cap per diem is $3 in Mozambique, right? That 70% of people live on less than $2 a day?
Of course it's going to be prepaid phones that are most used to discuss food prices - the people who can afford mobile phone contracts are going to be less impacted by the increases!